RE: SV: Generic emissions - EN 61000-6-3
It may be applied, but MUST it be applied? Does the OJ not still provide force to the use of the standard, or is that only in the EMC Directive? Jim Eichner, P.Eng. Manager, Engineering Services Xantrex Technology Inc. Mobile Power phone: (604) 422-2546 fax: (604) 420-1591 e-mail: jim.eich...@xantrex.com web: www.xantrex.com -Original Message- From: richwo...@tycoint.com [mailto:richwo...@tycoint.com] Sent: Tuesday, January 29, 2002 9:49 AM To: emc-p...@majordomo.ieee.org Subject: RE: SV: Generic emissions - EN 61000-6-3 As long as we are getting picky, let's don't forget that the Directives don't have a harmonized definition of what harmonized means. The defintion in the LVD does not include the need to be referenced in the OJ. Publication is for information only. Thus, a CENELEC safety standard may be applied as soon as it is ratified and presuption of conformity to the essential requirements is provided. Richard Woods Sensormatic Electronics Tyco International -Original Message- From: Brian Jones [mailto:e...@brianjones.co.uk] Sent: Tuesday, January 29, 2002 9:23 AM To: John Woodgate; emc-p...@majordomo.ieee.org Subject: Re: SV: Generic emissions - EN 61000-6-3 John, and everyone It is not true that all ENs are harmonised. The term, in this context, means specifically ENs which have been selected as relevant standards under one or more directives, and listed as such in the Official Journal. Thus, for example, basic standards are not harmonised. EN 61000-6-3, as a generic standard, will be listed in the OJ, but it is not in the current list published on 5 April 2001 as amended on 26 July 2001. It was published in October 2001 and will supersede EN 50081-1 on a date (the doc) which will be published when it is listed in the OJ. This may be the dow published in the front of the EN (1 July 2004) or may be a different date decided by the Commission. Note that there are differences between the IEC and EN versions. The following is an extract from the Commission's website http://europa.eu.int/comm/enterprise/newapproach/standardization/harmstds/vo rwort.html which explains in detail the extra requirements for harmonised standards. --- The New Approach directives are supported by harmonised standards which play a significant role in ensuring their application. Such standards have first the characteristics inherent to European Standards : The standards (typically EN, ETSs) are drafted by one of three European Standard Organisations (CEN,CENELEC, ETSI) The work is based on consensus Standards are adopted after a public inquiry with the national votes based on corresponding weighting features Standards remain voluntary but their transposition into national standards and the withdrawal of diverging national standards is mandatory according to the internal rules of the European Standards Organisations. Within the context of the New Approach additional conditions are superposed to the European Standards to cover the specific role of harmonised standards : The Commission issues a standardisation mandate according to the procedure of Directive 98/34/EC (consolidating Directive 83/189/EEC) The standards are developed in taking due account of the essential requirements The reference of the standard is published in the Official Journal with the indication of the Directive for which the presumption of conformity should apply Best wishes Brian Jones EMC Consultant and Competent Body Signatory - Original Message - From: John Woodgate j...@jmwa.demon.co.uk To: emc-p...@majordomo.ieee.org Sent: Tuesday, January 29, 2002 10:46 AM Subject: Re: SV: Generic emissions - EN 61000-6-3 I read in !emc-pstc that am...@westin-emission.no wrote (in LFENJLPMMJB mhpeibnilaehgccaa.am...@westin-emission.no) about 'SV: Generic emissions - EN 61000-6-3', on Tue, 29 Jan 2002: AFAIK EN61000-6-3 is not harmonized yet. ALL ENs are AUTOMATICALLY harmonized. I expect you mean that it may not have been 'notified' in the OJEC. I think it has. I have a problem to access the CENELEC web in order to check the current status of this standards. I have a copy of CISPR/CEI-IEC 1000-6-3:1996, Really? Then why have you not given the reference as '61000-6-3'? but I don't know if this issue is the latest version because the IEC site is also down for the moment. In this version they still describe 30-1000MHz radiated emission (same limits as in 81-1) and 0.15-30MHz conducted emission (same limits as in 81-1). That IS the latest (and only) issue. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. PLEASE do NOT copy news posts to me by E-MAIL
Re: SV: Generic emissions - EN 61000-6-3
I read in !emc-pstc that Brian Jones e...@brianjones.co.uk wrote (in 009001c1a8d0$c4fc0840$d841c0c1@oemcomputer) about 'SV: Generic emissions - EN 61000-6-3', on Tue, 29 Jan 2002: It is not true that all ENs are harmonised. The term, in this context, means specifically ENs which have been selected as relevant standards under one or more directives, and listed as such in the Official Journal. No, that is 'notified', not 'harmonized'. Thus, for example, basic standards are not harmonised. Ah, well now, this came up last week. We have to be VERY careful of the terminology. Basic EMC standards (EN61000-4-X) are not *notified*, but obviously they ARE harmonized otherwise there would be even more differences between test-house results in different countries.(;-) However, IEC Basic Safety Publications that are adopted as ENs, such as EN60529, CAN be, and usually are, notified. When harmonization was first introduced, it meant that national standards were brought into line with each other, maybe just in terms of technical requirements but preferably with identical texts. These documents were given 'harmonized' references, such as 'HD21.1 S2'. Some 600 still exist, but a large number have been *superseded by ENs*, which it is MANDATORY for the CENELEC members to implement as identical national standards (apart from Special National Conditions, normally to accommodate conflicting legal requirements). So these ENs are *even more harmonized*, de facto and de jure, than the HDs they replace or stand in place of. It would clearly be totally illogical to claim that HDs, which ARE harmonized by definition, are replaced by ENs which are more closely identical between member states but are not 'harmonized'. [snip] The following is an extract from the Commission's website http://europa.eu.int/comm/enterprise/newapproach/standardization/harmstds/vo rwort.html which explains in detail the extra requirements for harmonised standards. I don't see any 'extra requirements'. --- The New Approach directives are supported by harmonised standards which play a significant role in ensuring their application. Such standards have first the characteristics inherent to European Standards : The standards (typically EN, ETSs) are drafted by one of three European Standard Organisations (CEN,CENELEC, ETSI) The work is based on consensus Standards are adopted after a public inquiry with the national votes based on corresponding weighting features Standards remain voluntary but their transposition into national standards and the withdrawal of diverging national standards is mandatory according to the internal rules of the European Standards Organisations. All this is not 'special' or 'new' or 'additional' in any way, as far as ENs are concerned. Within the context of the New Approach additional conditions are superposed to the European Standards to cover the specific role of harmonised standards : This is typical Brussels Euroenglish, and it can easily be misinterpreted. The Commission issues a standardisation mandate according to the procedure of Directive 98/34/EC (consolidating Directive 83/189/EEC) The standards are developed in taking due account of the essential requirements This is about the *role* of harmonized standards developed in order to allow conformity with the standard to demonstrate compliance with a Directive. It does not, as far as I can see, change the *definition* of a harmonized standard in any way. The 'Euroenglish' bit is actually saying that the Commission *may not accept* an EN that was not produced under a standardization mandate and/or does not, in the Commission's opinion, address the essential requirements. Although it could be seen to attempt, with the words 'additional conditions', to throw the 'harmonized' status of such an EN into doubt, I doubt very much whether that would stick if challenged. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: SV: Generic emissions - EN 61000-6-3
John, and everyone It is not true that all ENs are harmonised. The term, in this context, means specifically ENs which have been selected as relevant standards under one or more directives, and listed as such in the Official Journal. Thus, for example, basic standards are not harmonised. EN 61000-6-3, as a generic standard, will be listed in the OJ, but it is not in the current list published on 5 April 2001 as amended on 26 July 2001. It was published in October 2001 and will supersede EN 50081-1 on a date (the doc) which will be published when it is listed in the OJ. This may be the dow published in the front of the EN (1 July 2004) or may be a different date decided by the Commission. Note that there are differences between the IEC and EN versions. The following is an extract from the Commission's website http://europa.eu.int/comm/enterprise/newapproach/standardization/harmstds/vo rwort.html which explains in detail the extra requirements for harmonised standards. --- The New Approach directives are supported by harmonised standards which play a significant role in ensuring their application. Such standards have first the characteristics inherent to European Standards : The standards (typically EN, ETSs) are drafted by one of three European Standard Organisations (CEN,CENELEC, ETSI) The work is based on consensus Standards are adopted after a public inquiry with the national votes based on corresponding weighting features Standards remain voluntary but their transposition into national standards and the withdrawal of diverging national standards is mandatory according to the internal rules of the European Standards Organisations. Within the context of the New Approach additional conditions are superposed to the European Standards to cover the specific role of harmonised standards : The Commission issues a standardisation mandate according to the procedure of Directive 98/34/EC (consolidating Directive 83/189/EEC) The standards are developed in taking due account of the essential requirements The reference of the standard is published in the Official Journal with the indication of the Directive for which the presumption of conformity should apply Best wishes Brian Jones EMC Consultant and Competent Body Signatory - Original Message - From: John Woodgate j...@jmwa.demon.co.uk To: emc-p...@majordomo.ieee.org Sent: Tuesday, January 29, 2002 10:46 AM Subject: Re: SV: Generic emissions - EN 61000-6-3 I read in !emc-pstc that am...@westin-emission.no wrote (in LFENJLPMMJB mhpeibnilaehgccaa.am...@westin-emission.no) about 'SV: Generic emissions - EN 61000-6-3', on Tue, 29 Jan 2002: AFAIK EN61000-6-3 is not harmonized yet. ALL ENs are AUTOMATICALLY harmonized. I expect you mean that it may not have been 'notified' in the OJEC. I think it has. I have a problem to access the CENELEC web in order to check the current status of this standards. I have a copy of CISPR/CEI-IEC 1000-6-3:1996, Really? Then why have you not given the reference as '61000-6-3'? but I don't know if this issue is the latest version because the IEC site is also down for the moment. In this version they still describe 30-1000MHz radiated emission (same limits as in 81-1) and 0.15-30MHz conducted emission (same limits as in 81-1). That IS the latest (and only) issue. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad
Re: SV: Generic emissions - EN 61000-6-3
I read in !emc-pstc that am...@westin-emission.no wrote (in LFENJLPMMJB mhpeibnilaehgccaa.am...@westin-emission.no) about 'SV: Generic emissions - EN 61000-6-3', on Tue, 29 Jan 2002: AFAIK EN61000-6-3 is not harmonized yet. ALL ENs are AUTOMATICALLY harmonized. I expect you mean that it may not have been 'notified' in the OJEC. I think it has. I have a problem to access the CENELEC web in order to check the current status of this standards. I have a copy of CISPR/CEI-IEC 1000-6-3:1996, Really? Then why have you not given the reference as '61000-6-3'? but I don't know if this issue is the latest version because the IEC site is also down for the moment. In this version they still describe 30-1000MHz radiated emission (same limits as in 81-1) and 0.15-30MHz conducted emission (same limits as in 81-1). That IS the latest (and only) issue. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
SV: Generic emissions - EN 61000-6-3
AFAIK EN61000-6-3 is not harmonized yet. I have a problem to access the CENELEC web in order to check the current status of this standards. I have a copy of CISPR/CEI-IEC 1000-6-3:1996, but I don't know if this issue is the latest version because the IEC site is also down for the moment. In this version they still describe 30-1000MHz radiated emission (same limits as in 81-1) and 0.15-30MHz conducted emission (same limits as in 81-1). I would suggest that you use EN50081-1 until it become harmonized. Amund -Opprinnelig melding- Fra: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]Pa vegne av Chris Chileshe Sendt: 28. januar 2002 15:41 Til: emc-p...@majordomo.ieee.org Emne: Generic emissions - EN 61000-6-3 Hi Group, I have just been touring the BSI website and discovered that the generic emissions standard EN 50081-1 for residential, commercial and light industrial, although current, has been superceded by EN 61000-6-3. If anyone has got a copy of this standard already, could they kindly advise - without resorting to replicating the entire standard on this forum!! - if there are major differences to be expected which would justify switching to this standard to avoid retesting in future - or is it a question of the emissions spectra now required for frequencies beyond 1GHz? Have the limits prescribed by EN50081-1 for the range 150kHz - 30Mhz - 1GHz stayed the same? Regards - Chris Chileshe - Ultronics Ltd - http://www.senstronics.com -Original Message- From: Chris Chileshe [SMTP:chris.chile...@ultronics.co.uk] Sent: Monday, January 28, 2002 9:11 AM To: emc-p...@majordomo.ieee.org Subject:RE: CE Marking - Prototypes Regarding products for demo's and exhibitions, Enci writes .. Therefore the application of CE Marking or lack thereof is meaningless. You would think so wouldn't you. A small problem arises in that if you have competitors with a CE marked product, they will make it a point to display this and this means potential customers will be signing deals with them and not you because they have better and more reliable information on delivery dates. If you have no competitors, then you are OK. CE marked or not, make sure that the product is safe and further, that it will not go bang when connected to a supply with everybody else's non compliant stuff. It might be an idea to take a large filter if one is affordable. There is nothing quite as memorable as a product that explodes at an exhibition. In fact, it makes the exhibition worth attending the next time, and considering it has been the talk of the industry since the last time, you will get an unusually large crowd, and a quick check through their business cards will reveal they are competitors and not customers if the former exist! Having said this much, I feel it important that I state that these experiences were not personal to me or my current or previous employers. That's the truth. Best regards - Chris -Original Message- From: Enci [SMTP:e...@cinepower.com] Sent: Sunday, January 27, 2002 12:18 PM To: emc-p...@majordomo.ieee.org Subject:RE: CE Marking - Protoypes Well, I found the guide I was looking for, and the key issue is the placing on the market or taking into service. The guide clearly states demonstrating at an exhibition is not considered to be placing on the market. It also says a notice is required, as descibed below. Therefore the application of CE Marking or lack thereof is meaningless. Enci Prototype, equipments for demostration aren't covered by the EMC or RTTE directive. This is article 8.2 of RTTE a similar article exist in the EMC directive 2. At trade fairs, exhibitions, demonstrations, etc., Member States shall not create any obstacles to the display of apparatus which does not comply with this Directive, provided that a visible sign clearly indicates that such apparatus may not be marketed or put into service until it has been made to comply. Ciao Paolo --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs
Generic emissions - EN 61000-6-3
Hi Group, I have just been touring the BSI website and discovered that the generic emissions standard EN 50081-1 for residential, commercial and light industrial, although current, has been superceded by EN 61000-6-3. If anyone has got a copy of this standard already, could they kindly advise - without resorting to replicating the entire standard on this forum!! - if there are major differences to be expected which would justify switching to this standard to avoid retesting in future - or is it a question of the emissions spectra now required for frequencies beyond 1GHz? Have the limits prescribed by EN50081-1 for the range 150kHz - 30Mhz - 1GHz stayed the same? Regards - Chris Chileshe - Ultronics Ltd - http://www.senstronics.com -Original Message- From: Chris Chileshe [SMTP:chris.chile...@ultronics.co.uk] Sent: Monday, January 28, 2002 9:11 AM To: emc-p...@majordomo.ieee.org Subject:RE: CE Marking - Prototypes Regarding products for demo's and exhibitions, Enci writes .. Therefore the application of CE Marking or lack thereof is meaningless. You would think so wouldn't you. A small problem arises in that if you have competitors with a CE marked product, they will make it a point to display this and this means potential customers will be signing deals with them and not you because they have better and more reliable information on delivery dates. If you have no competitors, then you are OK. CE marked or not, make sure that the product is safe and further, that it will not go bang when connected to a supply with everybody else's non compliant stuff. It might be an idea to take a large filter if one is affordable. There is nothing quite as memorable as a product that explodes at an exhibition. In fact, it makes the exhibition worth attending the next time, and considering it has been the talk of the industry since the last time, you will get an unusually large crowd, and a quick check through their business cards will reveal they are competitors and not customers if the former exist! Having said this much, I feel it important that I state that these experiences were not personal to me or my current or previous employers. That's the truth. Best regards - Chris -Original Message- From: Enci [SMTP:e...@cinepower.com] Sent: Sunday, January 27, 2002 12:18 PM To: emc-p...@majordomo.ieee.org Subject:RE: CE Marking - Protoypes Well, I found the guide I was looking for, and the key issue is the placing on the market or taking into service. The guide clearly states demonstrating at an exhibition is not considered to be placing on the market. It also says a notice is required, as descibed below. Therefore the application of CE Marking or lack thereof is meaningless. Enci Prototype, equipments for demostration aren't covered by the EMC or RTTE directive. This is article 8.2 of RTTE a similar article exist in the EMC directive 2. At trade fairs, exhibitions, demonstrations, etc., Member States shall not create any obstacles to the display of apparatus which does not comply with this Directive, provided that a visible sign clearly indicates that such apparatus may not be marketed or put into service until it has been made to comply. Ciao Paolo --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web
RE: Conducted Emissions---Sandy's Question and John's Question
Hi Richard, It is a test measurement product used in a telecom environment. So we often test DC conducted emissions on the 48VDC input to a hodge-podge combination of EN61326-1(which uses EN 55022 limits), 300386-X and certain customer specific EMC standards. Some of our customers reference obscure standards such as 300 132-2 paragraphs 4.9.x; these tests give the lab fits because we're the only customer that does it. I will look further into 300 386 for future products. I didn't spell all of that out in my previous email and I thank you for pointing out the error. Seems that I've been so busy lately that I've been doing everything in incomplete fashion...very frustrating. Chris -Original Message- From: Stone, Richard A (Richard) [SMTP:rsto...@lucent.com] Sent: Thursday, January 24, 2002 10:58 AM To: Chris Maxwell; emc-p...@majordomo.ieee.org Subject: RE: Conducted Emissions---Sandy's Question and John's Question Is this a telecommunications product? if so, then need DC conducted Emissions to new EU std. 300386. Done from 20khz to 30mhz. If product is ITE, then NO DC cond. is needed. Richard, -Original Message- From: Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: Wednesday, January 23, 2002 5:21 PM To: emc-p...@majordomo.ieee.org Subject: RE: Conducted Emissions---Sandy's Question and John's Question Hi guys, Remember, this is just my opinion. I work for a manufacturer, not a test lab; so this is a side job (a HUGE side job); not my life. For John: We do test the DC input of our rack-mount 48VDC products for conducted emissions. Many of our customers for these systems demand conducted emissions testing. The reasoning here is that these systems will operate from a DC mains which may operate many other products in the same rack or room. We use the same limits as for AC mains. However, we do not test the conducted emissions of the DC ports of our smaller products which run from wall-warts or bricks.For these products, we test the conducted emissions at the AC interface of the wall-wart or brick. For Sandy: When I test wall-warts for conducted emissions, I either plug them into the LISN directly or I use a short stub cable (about 6 long) made from Panel Components parts if I need to adapt the LISN output to a wall-wart with a non-US plug configuration. I then try to dress the wall-wart's cable in the configuration shown in the standard for dressing line cords. I'm sure there are other methods; but at least you have one opinion. Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: CE-test - Ing. Gert Gremmen - ce-marking and more... [SMTP:cet...@cetest.nl] Sent: Wednesday, January 23, 2002 2:10 PM To: John Stonier; emc-p...@majordomo.ieee.org Subject:RE: Conducted emission testing for EN55022 Hi John, EN 55022:1994 does not speak about DC power supplies. Other standards do. Normally the appropriate measurements are done on the AC supply side af any applied DC-power supply. The pitfall is that a good RF attenuating in the supply may hide the conducted emissions from your EUT, while another power supply may lead to serious spectrum problems. Your problem, because power supply manufactueres do not specify RF isolation classes. I suggest you to apply the test described using a basic transformer rectifier combination + simple stabilization circuit (if required), thereby minimizing attenuation and maximizing RF feedtrough. Take care to bridge the rectifier diodes with capacitors, otherwize thay might create interference themselves. Regards, Gert Gremmen, (Ing) Ce-test, qualified testing == Web presence http://www.cetest.nl/ CE-shop http://www.cetest.nl/ce_shop.htm /-/ Compliance testing is our core business /-/ == -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of John Stonier Sent: Wednesday, January 23, 2002 6:26 PM To: emc-p...@majordomo.ieee.org Subject: Conducted emission testing for EN55022 Hi folks My test lab's current interpretation of EN55022 is that DC Mains measurements are not required. Sections 56 specify measurements done on mains ports, but do not specify whether it applies to AC or DC mains. There is a reference in section nine that specifies conducted disturbance is measured between the phase lead and the reference ground, as well as the neutral lead and the reference ground. Does anyone know whether DC measurements are required for this standard
RE: Conducted Emissions---Sandy's Question and John's Question
Is this a telecommunications product? if so, then need DC conducted Emissions to new EU std. 300386. Done from 20khz to 30mhz. If product is ITE, then NO DC cond. is needed. Richard, -Original Message- From: Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: Wednesday, January 23, 2002 5:21 PM To: emc-p...@majordomo.ieee.org Subject: RE: Conducted Emissions---Sandy's Question and John's Question Hi guys, Remember, this is just my opinion. I work for a manufacturer, not a test lab; so this is a side job (a HUGE side job); not my life. For John: We do test the DC input of our rack-mount 48VDC products for conducted emissions. Many of our customers for these systems demand conducted emissions testing. The reasoning here is that these systems will operate from a DC mains which may operate many other products in the same rack or room. We use the same limits as for AC mains. However, we do not test the conducted emissions of the DC ports of our smaller products which run from wall-warts or bricks.For these products, we test the conducted emissions at the AC interface of the wall-wart or brick. For Sandy: When I test wall-warts for conducted emissions, I either plug them into the LISN directly or I use a short stub cable (about 6 long) made from Panel Components parts if I need to adapt the LISN output to a wall-wart with a non-US plug configuration. I then try to dress the wall-wart's cable in the configuration shown in the standard for dressing line cords. I'm sure there are other methods; but at least you have one opinion. Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: CE-test - Ing. Gert Gremmen - ce-marking and more... [SMTP:cet...@cetest.nl] Sent: Wednesday, January 23, 2002 2:10 PM To: John Stonier; emc-p...@majordomo.ieee.org Subject: RE: Conducted emission testing for EN55022 Hi John, EN 55022:1994 does not speak about DC power supplies. Other standards do. Normally the appropriate measurements are done on the AC supply side af any applied DC-power supply. The pitfall is that a good RF attenuating in the supply may hide the conducted emissions from your EUT, while another power supply may lead to serious spectrum problems. Your problem, because power supply manufactueres do not specify RF isolation classes. I suggest you to apply the test described using a basic transformer rectifier combination + simple stabilization circuit (if required), thereby minimizing attenuation and maximizing RF feedtrough. Take care to bridge the rectifier diodes with capacitors, otherwize thay might create interference themselves. Regards, Gert Gremmen, (Ing) Ce-test, qualified testing == Web presence http://www.cetest.nl/ CE-shop http://www.cetest.nl/ce_shop.htm /-/ Compliance testing is our core business /-/ == -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of John Stonier Sent: Wednesday, January 23, 2002 6:26 PM To: emc-p...@majordomo.ieee.org Subject: Conducted emission testing for EN55022 Hi folks My test lab's current interpretation of EN55022 is that DC Mains measurements are not required. Sections 56 specify measurements done on mains ports, but do not specify whether it applies to AC or DC mains. There is a reference in section nine that specifies conducted disturbance is measured between the phase lead and the reference ground, as well as the neutral lead and the reference ground. Does anyone know whether DC measurements are required for this standard? John Stonier File: Gert Gremmen.vcf --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc
Re: Harmonic current emissions
Dear Rich Many thanks for your useful analyses. I was wrong to suggest that the 'computer industry' is in denial about mains harmonics - I realise that many people in that industry have made and are making valuable contributions in that field. But I am sure that the claims that there is 'no scientific evidence' for harmonics problems would not stand the light of day. In the UK harmonic problems due to fluorescent lighting have been discussed in public fora since the 1950's, and Arrilaga's important textbook on harmonics was published in 1985. The IEE (based in London) held an international conference on harmonics in power systems in 1981. I haven't costed any PFC designs for a while, but there now appear to be solutions available that have much lower cost then the 'active PFC' front converters we used to use. For example: the 'charge-pump' method, which does not use additional switching devices - see Infineon Application Note: AN-TDA 1684X (version 1.2 dated June 2000) and a (probably) forthcoming article on improving this technique in a future issue of Compliance Engineering Magazine (www.ce-mag.com). Regards, Keith Armstrong In a message dated 23/01/02 20:11:32 GMT Standard Time, ri...@sdd.hp.com writes: Subj:Harmonic current emissions Date:23/01/02 20:11:32 GMT Standard Time From:ri...@sdd.hp.com (Rich Nute) Sender:owner-emc-p...@majordomo.ieee.org Reply-to: A HREF=mailto:ri...@sdd.hp.com;ri...@sdd.hp.com/A (Rich Nute) To:cherryclo...@aol.com CC:ghery.pet...@intel.com, emc-p...@majordomo.ieee.org Hi Keith and Ghery: There are a number of effects of harmonic current emission from non-linear loads. 1) When a large number of loads rich in triplen harmonics are supplied from a 3-phase source, the neutral current can be as high as root 3 of the phase current. (This effect does not exist on a single-phase distribution system, or on a 3-phase system where each phase has its own neutral.) Where the neutral wire is sized for a balanced load, some authorities allow the neutral wire to be one size smaller than the phase wire. Such a wire is likely to be overheated by the triplen currents. Indeed, it is possible to overheat the neutral wire when it is sized the same as the phase wire. In the USA, authorities now require (for such loads) the wire to be larger than the phase wire, or two, parallel neutral wires. 2) Consider that the non-linear load generates current at harmonics of the mains frequency and injects it into the mains distribution system. This current must circulate in the distribution system and return to the source (load). Often, this current circulates in the delta primary of the first upstream delta-wye distribution transformer, and causes the transformer delta winding to overheat. (This effect is likewise mostly due to triplen harmonics.) In the USA, distribution transformers are specially designed to dissipate this power without overheating. Such transformers include a K-factor rating, which is a measure of the transformer to accommodate the current. 3) Depending on the source impedance, a large number of non-linear loads can cause voltage waveform distortion. Voltage distortion is caused by all of the harmonics, not just the triplen harmonics. Voltage waveform distortion can cause motors to overheat. Each of these effects is a separate and independent issue. They should not be lumped as a single issue. For each effect, there can be one or more remedies. The remedy can be either in the load or in the source. EN 61000-3-2 arises from the voltage distortion effect. Mr. Van den Bergh's comments (as quoted by Keith) appear to address voltage distortion, not the other effects. Because of the difference in the design of power distribution systems, voltage distortion is more of a problem in the EU than in the USA. I suspect the real reason for the computer industry's denial of harmonics problems, or else blaming them on a poor distribution system, is that US computer manufacturers simply want to make one model they can sell world-wide so they want whatever is permitted in their main market (the US) to be permitted everywhere else. Would you agree with this? I believe this is an oversimplification of the manufacturer's dilemma of addressing this problem. The USA computer industry has been quite forward in addressing effects 1 and 2. The computer industry was the force behind a series of academia-based seminars on the causes and solutions to effects 1 and 2 that resulted in changes to the USA National Electrical Code and to distribution transformer testing and ratings. (I presented in some of those seminars.) This is NOT denial. But whichever
Re: Harmonic current emissions
I read in !emc-pstc that Rich Nute ri...@sdd.hp.com wrote (in 200201232308.paa21...@epgc264.sdd.hp.com) about 'Harmonic current emissions', on Wed, 23 Jan 2002: The additional cost for a PF-corrected SMPS is not a constant adder; it is proportional to power output. One must use higher power PF components for higher power output. But the whole cost is roughly proportional to power. The figures I quoted refer to 'a normal PC power supply', which I suppose is a 200 or 250 W unit. Having actually purchased production quantities (1995) of the same SMPS in both non-PF-corrected and PF- corrected schemes, the additional cost for PF-corrected ranged from 50% to 75% higher than the non-PF-corrected supply. In 1995, corrected supplies were relatively new and quantities were low. When the CDV for the Millennium Amendment was circulated, we in UK had protests from power supply manufacturers, saying that it undermined their market for corrected supplies, **which they were almost entirely concentrating on**. In fact, of course, the majority of their sales still go into Class D products. More recently (2001), the cost difference was indeed lower -- only about 25-30% premium. That still seems high. How does it compare with my USD figures, though? (;-) I suspect your sources wanted to sell PF-corrected SMPS's and exaggerated on the low side. The figures I quoted did not come from a sales situation but information supplied to the IEC WG. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: Harmonic current emissions
Hi John: But whichever method is adopted, the customer pays the bill eventually and I have more confidence in the highly competitive world of electronic products to come up with a cost-effective solution in a timely manner. One of the USA's major objections to EN61003-2 is that remedying the load repeats with each new product that is introduced, while remedying the source is a one-time remedy. EN61000-3-2 requires continous cost to the consumer with each product. (The cost is NOT trivial -- nearly double the cost of the power supply.) No, that's certainly an exaggeration. We have been told various sums from USD1 to USD5, and I suspect that the lower value is nearer the truth. The additional cost for a PF-corrected SMPS is not a constant adder; it is proportional to power output. One must use higher power PF components for higher power output. Having actually purchased production quantities (1995) of the same SMPS in both non-PF-corrected and PF- corrected schemes, the additional cost for PF-corrected ranged from 50% to 75% higher than the non-PF-corrected supply. More recently (2001), the cost difference was indeed lower -- only about 25-30% premium. I suspect your sources wanted to sell PF-corrected SMPS's and exaggerated on the low side. Rich --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: Conducted Emissions---Sandy's Question and John's Question
Hi guys, Remember, this is just my opinion. I work for a manufacturer, not a test lab; so this is a side job (a HUGE side job); not my life. For John: We do test the DC input of our rack-mount 48VDC products for conducted emissions. Many of our customers for these systems demand conducted emissions testing. The reasoning here is that these systems will operate from a DC mains which may operate many other products in the same rack or room. We use the same limits as for AC mains. However, we do not test the conducted emissions of the DC ports of our smaller products which run from wall-warts or bricks.For these products, we test the conducted emissions at the AC interface of the wall-wart or brick. For Sandy: When I test wall-warts for conducted emissions, I either plug them into the LISN directly or I use a short stub cable (about 6 long) made from Panel Components parts if I need to adapt the LISN output to a wall-wart with a non-US plug configuration. I then try to dress the wall-wart's cable in the configuration shown in the standard for dressing line cords. I'm sure there are other methods; but at least you have one opinion. Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: CE-test - Ing. Gert Gremmen - ce-marking and more... [SMTP:cet...@cetest.nl] Sent: Wednesday, January 23, 2002 2:10 PM To: John Stonier; emc-p...@majordomo.ieee.org Subject: RE: Conducted emission testing for EN55022 Hi John, EN 55022:1994 does not speak about DC power supplies. Other standards do. Normally the appropriate measurements are done on the AC supply side af any applied DC-power supply. The pitfall is that a good RF attenuating in the supply may hide the conducted emissions from your EUT, while another power supply may lead to serious spectrum problems. Your problem, because power supply manufactueres do not specify RF isolation classes. I suggest you to apply the test described using a basic transformer rectifier combination + simple stabilization circuit (if required), thereby minimizing attenuation and maximizing RF feedtrough. Take care to bridge the rectifier diodes with capacitors, otherwize thay might create interference themselves. Regards, Gert Gremmen, (Ing) Ce-test, qualified testing == Web presence http://www.cetest.nl/ CE-shop http://www.cetest.nl/ce_shop.htm /-/ Compliance testing is our core business /-/ == -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of John Stonier Sent: Wednesday, January 23, 2002 6:26 PM To: emc-p...@majordomo.ieee.org Subject: Conducted emission testing for EN55022 Hi folks My test lab's current interpretation of EN55022 is that DC Mains measurements are not required. Sections 56 specify measurements done on mains ports, but do not specify whether it applies to AC or DC mains. There is a reference in section nine that specifies conducted disturbance is measured between the phase lead and the reference ground, as well as the neutral lead and the reference ground. Does anyone know whether DC measurements are required for this standard? John Stonier File: Gert Gremmen.vcf --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: Harmonic current emissions
I read in !emc-pstc that Rich Nute ri...@sdd.hp.com wrote (in 200201232003.maa21...@epgc264.sdd.hp.com) about 'Harmonic current emissions', on Wed, 23 Jan 2002: Hi Keith and Ghery: There are a number of effects of harmonic current emission from non-linear loads. 1) When a large number of loads rich in triplen harmonics are supplied from a 3-phase source, the neutral current can be as high as root 3 of the phase current. (This effect does not exist on a single-phase distribution system, or on a 3-phase system where each phase has its own neutral.) Consider that the 3rd harmonic current of a high-efficiency single-phase rectifier is near 90% of the fundamental. Then consider that the third harmonic currents *add arithmetically* in the neutral. That give a neutral current of 2.7 times the fundamental current. If you take all the triplen harmonics into account you get a neutral current of 2.85.. times the fundamental current in one phase. [snip] The USA computer industry has been quite forward in addressing effects 1 and 2. The computer industry was the force behind a series of academia-based seminars on the causes and solutions to effects 1 and 2 that resulted in changes to the USA National Electrical Code and to distribution transformer testing and ratings. (I presented in some of those seminars.) This is NOT denial. But whichever method is adopted, the customer pays the bill eventually and I have more confidence in the highly competitive world of electronic products to come up with a cost-effective solution in a timely manner. One of the USA's major objections to EN61003-2 is that remedying the load repeats with each new product that is introduced, while remedying the source is a one-time remedy. EN61000-3-2 requires continous cost to the consumer with each product. (The cost is NOT trivial -- nearly double the cost of the power supply.) No, that's certainly an exaggeration. We have been told various sums from USD1 to USD5, and I suspect that the lower value is nearer the truth. Indeed, this has forced manufacturers to develop one supply for the EU, and one supply for the remainder of the world. And, forced two products for the world instead of one. (One of the benefits of EN61000-3-2 has been a real effort at power reduction so that more and more products are below the 50-watt exemption limit.) 75 W. A change to 50 W would need a new vote by national standards committees, as is clarified in the Millennium Amendment. [snip] -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Harmonic current emissions
Hi Keith and Ghery: There are a number of effects of harmonic current emission from non-linear loads. 1) When a large number of loads rich in triplen harmonics are supplied from a 3-phase source, the neutral current can be as high as root 3 of the phase current. (This effect does not exist on a single-phase distribution system, or on a 3-phase system where each phase has its own neutral.) Where the neutral wire is sized for a balanced load, some authorities allow the neutral wire to be one size smaller than the phase wire. Such a wire is likely to be overheated by the triplen currents. Indeed, it is possible to overheat the neutral wire when it is sized the same as the phase wire. In the USA, authorities now require (for such loads) the wire to be larger than the phase wire, or two, parallel neutral wires. 2) Consider that the non-linear load generates current at harmonics of the mains frequency and injects it into the mains distribution system. This current must circulate in the distribution system and return to the source (load). Often, this current circulates in the delta primary of the first upstream delta-wye distribution transformer, and causes the transformer delta winding to overheat. (This effect is likewise mostly due to triplen harmonics.) In the USA, distribution transformers are specially designed to dissipate this power without overheating. Such transformers include a K-factor rating, which is a measure of the transformer to accommodate the current. 3) Depending on the source impedance, a large number of non-linear loads can cause voltage waveform distortion. Voltage distortion is caused by all of the harmonics, not just the triplen harmonics. Voltage waveform distortion can cause motors to overheat. Each of these effects is a separate and independent issue. They should not be lumped as a single issue. For each effect, there can be one or more remedies. The remedy can be either in the load or in the source. EN 61000-3-2 arises from the voltage distortion effect. Mr. Van den Bergh's comments (as quoted by Keith) appear to address voltage distortion, not the other effects. Because of the difference in the design of power distribution systems, voltage distortion is more of a problem in the EU than in the USA. I suspect the real reason for the computer industry's denial of harmonics problems, or else blaming them on a poor distribution system, is that US computer manufacturers simply want to make one model they can sell world-wide so they want whatever is permitted in their main market (the US) to be permitted everywhere else. Would you agree with this? I believe this is an oversimplification of the manufacturer's dilemma of addressing this problem. The USA computer industry has been quite forward in addressing effects 1 and 2. The computer industry was the force behind a series of academia-based seminars on the causes and solutions to effects 1 and 2 that resulted in changes to the USA National Electrical Code and to distribution transformer testing and ratings. (I presented in some of those seminars.) This is NOT denial. But whichever method is adopted, the customer pays the bill eventually and I have more confidence in the highly competitive world of electronic products to come up with a cost-effective solution in a timely manner. One of the USA's major objections to EN61003-2 is that remedying the load repeats with each new product that is introduced, while remedying the source is a one-time remedy. EN61000-3-2 requires continous cost to the consumer with each product. (The cost is NOT trivial -- nearly double the cost of the power supply.) Indeed, this has forced manufacturers to develop one supply for the EU, and one supply for the remainder of the world. And, forced two products for the world instead of one. (One of the benefits of EN61000-3-2 has been a real effort at power reduction so that more and more products are below the 50-watt exemption limit.) I have some knowledge of power-factor correction techniques in switch-mode supplies, and some of them can cost very little indeed. So I really don't know why the US computer industry is making such a fuss about controlling harmonic emissions. I certainly have not seen low-cost PF correction techniques. My experience is that the cost is nearly twice the cost of a non-PF corrected power supply. Best regards, Rich ps: EU power suppliers are taking an interesting approach to their customers. If the customer has a linear power factor problem, we will correct it. If the customer has a non-linear power factor problem, we will not correct for it, and we will not sell power to you if the effect is too great. Clearly a monopolistic view
Conducted Emissions Question
HI all, I have a question regarding performing conducted emissions on a wall mount power supply. When looking at EN 55022 test setup it shows EUT on tabletop with 80 cms from EUT to AMN and bundled cord between AMN and EUT. If you where testing a wall mount power supply does anyone feel that the specification supports letting you put an extension cable between wall mount power supply and LISN to meet this setup. In essence the question is, Does a wall mount power supply have to be tested plugged directly into the LISN. By inserting the cable between supply and LISN you are adding inductance and results are a few dB better. Also you could argue that wall mount supply should be plugged into LISN to replicate actual usage. I know that I may have answered my own question but am interested if anyone else believes putting extension cord between LISN and wall mount supply is reasonable. As usual colleagues, thanks in advance for your thoughts. Sandy Mazzola Santo Mazzola Regulatory Engineer Symbol Technologies Inc 1 Symbol Plaza Holtsville, N. Y. 11742-1300 Phone: (631) 738-5373 Fax: (631) 738-3318 E-mail: mazzo...@symbol.com BEGIN:VCARD VERSION:2.1 X-GWTYPE:USER FN:Mazzola, Sandy TEL;WORK:(631) 738-5373 EMAIL;WORK;PREF;NGW:mazzo...@symbol.com N:Mazzola;Sandy X-GWUSERID:MazzolaS END:VCARD BEGIN:VCARD VERSION:2.1 X-GWTYPE:USER FN:Mazzola, Sandy TEL;WORK:(631) 738-5373 EMAIL;WORK;PREF;NGW:mazzo...@symbol.com N:Mazzola;Sandy X-GWUSERID:MazzolaS END:VCARD
Re: Required separation between item with 3V/m radiated immunity and Class A (industrial) emissions?
My own personal experience bears this out. on 1/10/02 3:39 PM, Patrick Lawler at plaw...@west.net wrote: I belive emissions standards were designed to allow proper operation of radios and televisions with minimal irritation. This would include sound and video quality. I heard this story a long time ago with respect to FCC limits. On the other hand, immunity standards were developed so equipment would not be damaged, not 'lock up', and remain safe. While equipment might meet a 3V/m immunity standard, I'll bet if it was an 'Intentional Receiver' like a radio (there are international radiators, why not intentional receivers?), it would operate poorly when separated by 1m from a CISPR Class A noise source. Obviously, this assumes the noise was comparable in frequency to the victim equipment. On Thu, 10 Jan 2002 14:18:37 +1000, peter.pou...@invensys.com wrote: At the moment I'm examining as a generic case, the potential for interference with Item A (tested to comply with 3V/m radiated immunity) caused by Item B (tested to comply with FCC or EN Class A [industrial] emissions). Using simple inverse distance ( E2 = E1 x d1/d2 ) extrapolation (assuming dominant interfering frequencies will be in the far field), I come up with a required separation distance of approximately 75cm to ensure the 3V/m immunity limit of Item A isn't exceeded by the 47dBuV/m emissions from Item B. Based on this, I'd expect then the risk for EMC problems should be relatively low provided: 1. A minimum separation of 1m was used between Items A B; 2. No direct interconnection of A to B via cables; 3. Use of a mains filter and/or separate power supply sources for A B; 4. The nature of Item B is such that no significant low (eg.power) frequency magnetic fields are emitted; Does anyone have any experience to suggest that the minimum separation of 1m under theses conditions would not be adequate? --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: Required separation between item with 3V/m radiated immunity and Class A (industrial) emissions?
I belive emissions standards were designed to allow proper operation of radios and televisions with minimal irritation. This would include sound and video quality. I heard this story a long time ago with respect to FCC limits. On the other hand, immunity standards were developed so equipment would not be damaged, not 'lock up', and remain safe. While equipment might meet a 3V/m immunity standard, I'll bet if it was an 'Intentional Receiver' like a radio (there are international radiators, why not intentional receivers?), it would operate poorly when separated by 1m from a CISPR Class A noise source. Obviously, this assumes the noise was comparable in frequency to the victim equipment. On Thu, 10 Jan 2002 14:18:37 +1000, peter.pou...@invensys.com wrote: At the moment I'm examining as a generic case, the potential for interference with Item A (tested to comply with 3V/m radiated immunity) caused by Item B (tested to comply with FCC or EN Class A [industrial] emissions). Using simple inverse distance ( E2 = E1 x d1/d2 ) extrapolation (assuming dominant interfering frequencies will be in the far field), I come up with a required separation distance of approximately 75cm to ensure the 3V/m immunity limit of Item A isn't exceeded by the 47dBuV/m emissions from Item B. Based on this, I'd expect then the risk for EMC problems should be relatively low provided: 1. A minimum separation of 1m was used between Items A B; 2. No direct interconnection of A to B via cables; 3. Use of a mains filter and/or separate power supply sources for A B; 4. The nature of Item B is such that no significant low (eg.power) frequency magnetic fields are emitted; Does anyone have any experience to suggest that the minimum separation of 1m under theses conditions would not be adequate? --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Required separation between item with 3V/m radiated immunity and Class A (industrial) emissions?
Hi Folks. At the moment I'm examining as a generic case, the potential for interference with Item A (tested to comply with 3V/m radiated immunity) caused by Item B (tested to comply with FCC or EN Class A [industrial] emissions). Using simple inverse distance ( E2 = E1 x d1/d2 ) extrapolation (assuming dominant interfering frequencies will be in the far field), I come up with a required separation distance of approximately 75cm to ensure the 3V/m immunity limit of Item A isn't exceeded by the 47dBuV/m emissions from Item B. Based on this, I'd expect then the risk for EMC problems should be relatively low provided: 1. A minimum separation of 1m was used between Items A B; 2. No direct interconnection of A to B via cables; 3. Use of a mains filter and/or separate power supply sources for A B; 4. The nature of Item B is such that no significant low (eg.power) frequency magnetic fields are emitted; Does anyone have any experience to suggest that the minimum separation of 1m under theses conditions would not be adequate? Thanks, Peter Poulos Design Engineer Foxboro Transportation (Invensys Rail Systems Australia) --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Noise emissions of outdoor equipment
This won't affect most of the people on this mailing list, but some may be interested. Directive 2000/14/EC of the European Parliament and the Council of 8 May 2000 on the approximation of the laws of the Member States relating to the noise emission in the environment by equipment for use outdoors requires noise labelling for around 60 different types of machinery used outdoors, from lawn mowers to drill rigs. The directive also makes some categories of equipment subject to maximum noise limits. The directive comes into force on 1 January 2002. The Directive is quite restrictive in the way in which standardised measurement techniques must be applied and documented. As anyone who knows about noise and vibration measurement will confirm, this is potentially fraught with difficulty due to possible variations in the test equipment and the way it is used. I've recently been looking into obtaining some specialist training in this area, and have obtained a quote for a day's training course specially tailored our staff. However, there are only a couple of us here who would benefit from the training and this makes it potentially uneconomic for us to proceed. I'd be interested in hearing from anyone else who might want to participate in the training course so as to spread the cost. The training would take place at or near our office in Derbyshire and will cost of the order of GBP300 per person for the day it would take. We can arrange accommodation and meals as part of the deal. Please contact me off list if you're interested. Regards Nick. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: Conducted emissions - frequencies lower than 150kHz
One mink, two mink, three mink (preferred). Or minks. My unabridged Random House states that the plural is mink, but minks may be used, especially when referred collectively. Personally, I prefer minkies ! It would not surprise me that some 10-20 years from now minks would be widely used and, therefore, end up legitimately in the dictionary. On the other hand, if someone has a more recent dictionary than my own, I wouldn't be surprised if that is already there. Could it be that the word gurus want to avoid confusing minks with minx, an entirely different animal taniagr...@msn.com - Original Message - From: Chris Chileshe Sent: Friday, November 16, 2001 7:45 AM To: 'Ken Javor'; Nerad, Daren HS-SNS; 'John Woodgate'; emc-p...@majordomo.ieee.org Subject: RE: Conducted emissions - frequencies lower than 150kHz Is Minks the plural for 'Mink' or is it always Mink in both singular and plural? Have I been misinformed? Regards - Chris _ This message has been checked for all known viruses by Star Internet delivered through the MessageLabs Virus Scanning Service. For further information visit http://www.star.net.uk/stats.asp or alternatively call Star Internet for details on the Virus Scanning Service. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: Conducted emissions - frequencies lower than 150kHz
Is Minks the plural for 'Mink' or is it always Mink in both singular and plural? Have I been misinformed? Regards - Chris _ This message has been checked for all known viruses by Star Internet delivered through the MessageLabs Virus Scanning Service. For further information visit http://www.star.net.uk/stats.asp or alternatively call Star Internet for details on the Virus Scanning Service. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: Radiated Emissions EUT Config
I read in !emc-pstc that Scott Lemon sle...@caspiannetworks.com wrote (in 3be064c5.e48c3...@caspiannetworks.com) about 'Radiated Emissions EUT Config', on Wed, 31 Oct 2001: I am in search of opinions regarding the acceptable EUT configuration for radiated emissions testing. If a system is comprised of one or more independent shelf-level products (e.g. one shelf in a rack or several racks full), at what level is it acceptable to test? Assume that the system can be sold as one independent fully functional shelf or as numerous interconnected shelves (interconnection just increasing system capacity). For example, one shelf could be sold and deployed, then 6 months later another shelf added (cabled up to the first), and so on, etc. 1. Would it be acceptable to test at the shelf level? 2. If not, where is the line drawn? Two? Ten? In a typical CO you may see racks and racks of the same equipment shelves/chassis - chances are, they were not all tested together - where is it reasonable to stop? FCC (ref. ANSI C63.4)/EN300386/GR1089 have some guidance, differing slightly, but not clear. Any and all opinions/experiences from the group are welcome. Adopt a 'real world' approach. If the separate products could be simply placed side-by-side or stacked on a table or shelf, instead of being mounted in a rack, you do not need to measure the rack as a whole. See IEC/EN61000-3-2, which says this explicitly. In Europe, the question should not arise, because since each product can be marketed separately, each requires to conform to applicable standards and to be CE marked. Assembly into a rack could be carried out by anyone - an installer or end-user - and clearly to then require re-testing would be unrealistic. The only snag is that if the **manufacturer** assembles the products into a rack, **and then markets the rack as a single article of commerce, i.e. at an inclusive price**, then it is classed as a system under the EMC Directive and DOES need to conform as a whole to the applicable standards, unless the product standard says differently, as CISPR15/EN55015 does for dimmers. Large assemblies and aggregations are almost always more or less 'site- specific' and are thus 'installations' under the EMC Directive. Installations need no a priori testing but the installation must be in accordance with the product manufacturers' instructions, including the correct use of appropriate cables. Installations are assessed for EMC only in case of complaint (of either excessive emission or inadequate immunity). -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Eat mink and be dreary! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Radiated Emissions EUT Config
Hello Group, I am in search of opinions regarding the acceptable EUT configuration for radiated emissions testing. If a system is comprised of one or more independent shelf-level products (e.g. one shelf in a rack or several racks full), at what level is it acceptable to test? Assume that the system can be sold as one independent fully functional shelf or as numerous interconnected shelves (interconnection just increasing system capacity). For example, one shelf could be sold and deployed, then 6 months later another shelf added (cabled up to the first), and so on, etc. 1. Would it be acceptable to test at the shelf level? 2. If not, where is the line drawn? Two? Ten? In a typical CO you may see racks and racks of the same equipment shelves/chassis - chances are, they were not all tested together - where is it reasonable to stop? FCC (ref. ANSI C63.4)/EN300386/GR1089 have some guidance, differing slightly, but not clear. Any and all opinions/experiences from the group are welcome. Thanks and Regards, Scott Lemon Caspian Networks --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: Keep off the grass: RF emissions!
I read in !emc-pstc that Lothar Schmidt lothar.schm...@cetecomusa.com wrote (in 5EFB06767D7DD211828C0008C74CE95B414D40@CALVIN) about 'Keep off the grass: RF emissions!', on Mon, 29 Oct 2001: I guess the EN 55014-1,2 would be more applicable regarding EMC in Europe. They are written very largely around products that have at least a mains lead and often other external cables. I suppose the robot lawn-mower does not have external cables. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Eat mink and be dreary! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: Keep off the grass: RF emissions!
John, Massimo I guess the EN 55014-1,2 would be more applicable regarding EMC in Europe. However the ETSI depending on the answers from Massimo can cover already a good part and should be seen in combination to the EN. Best Regards Lothar Schmidt Technical Manager EMC/Radio BQB CETECOM Inc. 411 Dixon Landing Road Milpitas, CA 95035 * +1 408 586 6214 * +1 408 586 6299 -Original Message- From: John Woodgate [mailto:j...@jmwa.demon.co.uk] Sent: Monday, October 29, 2001 8:39 AM To: emc-p...@majordomo.ieee.org Subject: Re: Keep off the grass: RF emissions! I read in !emc-pstc that Massimo Polignano massimo.polign...@esaote.com wrote (in OFB42F2B94.C5CABD33-ONC1256AF4 ..00369...@esaote.com) about 'Keep off the grass: RF emissions!', on Mon, 29 Oct 2001: Is there any applicable product standard dealing with EMC and safety of that kind of devices? In Europe, the Generic EMC Standards would apply plus whatever ETSI standards cover the radio part. For safety, I suppose EN60335-1 if the propulsion is electric. Do you think it is to be handled as an intentional RF transmitter, similarly to an ISM? Yes. Unless it's actually an induction system rather than an EM-wave system, in which case the answer gets less definite. What frequency does the transmitter use? Let's consider it is not an intentional transmitter, as the emission depends on the broadness of the reference loop, does it make sense to do measurement at three or ten meters? You probably need to measure the magnetic field if the transmitter has a loop antenna, not the electric field, so the 3m/10m distance requirement is not relevant. But there probably needs to be a specified distance, maybe 1 m. Do you think immunity as well can be anlysed regardless the actual installation? Immunity is VERY important. We don't want these things running amok every time an EM disturbance occurs! -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Eat mink and be dreary! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: Keep off the grass: RF emissions!
I read in !emc-pstc that Massimo Polignano massimo.polign...@esaote.com wrote (in OFB42F2B94.C5CABD33-ONC1256AF4 ..00369...@esaote.com) about 'Keep off the grass: RF emissions!', on Mon, 29 Oct 2001: Is there any applicable product standard dealing with EMC and safety of that kind of devices? In Europe, the Generic EMC Standards would apply plus whatever ETSI standards cover the radio part. For safety, I suppose EN60335-1 if the propulsion is electric. Do you think it is to be handled as an intentional RF transmitter, similarly to an ISM? Yes. Unless it's actually an induction system rather than an EM-wave system, in which case the answer gets less definite. What frequency does the transmitter use? Let's consider it is not an intentional transmitter, as the emission depends on the broadness of the reference loop, does it make sense to do measurement at three or ten meters? You probably need to measure the magnetic field if the transmitter has a loop antenna, not the electric field, so the 3m/10m distance requirement is not relevant. But there probably needs to be a specified distance, maybe 1 m. Do you think immunity as well can be anlysed regardless the actual installation? Immunity is VERY important. We don't want these things running amok every time an EM disturbance occurs! -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Eat mink and be dreary! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: Keep off the grass: RF emissions!
I saw a piece on on this type of mower on one of the Dateline or other news formats. The one displayed also had the ability to be operated remotely by the owner to trim etc. In this case, the hand held transmitter would be an intentional radiator. George Alspaugh -- Forwarded by George Alspaugh/Lex/Lexmark on 10/29/2001 11:30 AM --- woods%sensormatic@interlock.lexmark.com on 10/29/2001 10:09:45 AM Please respond to woods%sensormatic@interlock.lexmark.com To: emc-pstc%majordomo.ieee@interlock.lexmark.com cc:(bcc: George Alspaugh/Lex/Lexmark) Subject: RE: Keep off the grass: RF emissions! If it is an intentional radiator and operates above 9 kHz, it is considered to be a transmitter. If so, it is considered to be an inductive loop short range device in Europe and subject to EN 300330-1 and -2 for radio emissions and EN 301489-1 and -3 for spurious emissions and immunity. FCC Part 15 rules applies in the US and Industry Canada RSS-210 applies in Canada. However, one might be able to construct a reasonable argument that the device is not an intentional radiator because the signal is inductively coupled to the mower and that any emissions outside the boundary is unintentional. The problem with the argument is that the loop and mower are not physically attached or in proximity all of the time. Richard Woods Sensormatic Electronics -Original Message- From: Massimo Polignano [mailto:massimo.polign...@esaote.com] Sent: Monday, October 29, 2001 9:08 AM To: emc-p...@majordomo.ieee.org Subject: Keep off the grass: RF emissions! Hello everybody! A friend of mine, overthinking of the breadth of my knowledge, is asking me for some advise about the applicable standards to a rather unusual piece of equipment. It is a auto mower intended to be programmed by the user to cut within a given garden area. It makes use of a boundary loop wire to exchange information (by means of RF TX-RX) about the actual position and the cutting area. It is provided also with a docking station where it goes automatically to recharge its battery. Now the questions. Is there any applicable product standard dealing with EMC and safety of that kind of devices? Do you think it is to be handled as an intentional RF transmitter, similarly to an ISM? Let's consider it is not an intentional transmitter, as the emission depends on the broadness of the reference loop, does it make sense to do measurement at three or ten meters? Do you think immunity as well can be anlysed regardless the actual installation? As my field of interest is bounded to electromedical devices and actually I have no garden to take care of, can someone out of there help my friend to send this problem to grass? Thanks in advance. m.p. - ESAOTE S.p.A. Massimo Polignano Research Product DevelopmentDesign Quality Control Mngr Via di Caciolle,15tel:+39.055.4229402 I- 50127 Florence fax:+39.055.4223305 e-mail: massimo.polign...@esaote.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: Keep off the grass: RF emissions!
If it is an intentional radiator and operates above 9 kHz, it is considered to be a transmitter. If so, it is considered to be an inductive loop short range device in Europe and subject to EN 300330-1 and -2 for radio emissions and EN 301489-1 and -3 for spurious emissions and immunity. FCC Part 15 rules applies in the US and Industry Canada RSS-210 applies in Canada. However, one might be able to construct a reasonable argument that the device is not an intentional radiator because the signal is inductively coupled to the mower and that any emissions outside the boundary is unintentional. The problem with the argument is that the loop and mower are not physically attached or in proximity all of the time. Richard Woods Sensormatic Electronics -Original Message- From: Massimo Polignano [mailto:massimo.polign...@esaote.com] Sent: Monday, October 29, 2001 9:08 AM To: emc-p...@majordomo.ieee.org Subject: Keep off the grass: RF emissions! Hello everybody! A friend of mine, overthinking of the breadth of my knowledge, is asking me for some advise about the applicable standards to a rather unusual piece of equipment. It is a auto mower intended to be programmed by the user to cut within a given garden area. It makes use of a boundary loop wire to exchange information (by means of RF TX-RX) about the actual position and the cutting area. It is provided also with a docking station where it goes automatically to recharge its battery. Now the questions. Is there any applicable product standard dealing with EMC and safety of that kind of devices? Do you think it is to be handled as an intentional RF transmitter, similarly to an ISM? Let's consider it is not an intentional transmitter, as the emission depends on the broadness of the reference loop, does it make sense to do measurement at three or ten meters? Do you think immunity as well can be anlysed regardless the actual installation? As my field of interest is bounded to electromedical devices and actually I have no garden to take care of, can someone out of there help my friend to send this problem to grass? Thanks in advance. m.p. - ESAOTE S.p.A. Massimo Polignano Research Product DevelopmentDesign Quality Control Mngr Via di Caciolle,15tel:+39.055.4229402 I- 50127 Florence fax:+39.055.4223305 e-mail: massimo.polign...@esaote.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Keep off the grass: RF emissions!
Hello everybody! A friend of mine, overthinking of the breadth of my knowledge, is asking me for some advise about the applicable standards to a rather unusual piece of equipment. It is a auto mower intended to be programmed by the user to cut within a given garden area. It makes use of a boundary loop wire to exchange information (by means of RF TX-RX) about the actual position and the cutting area. It is provided also with a docking station where it goes automatically to recharge its battery. Now the questions. Is there any applicable product standard dealing with EMC and safety of that kind of devices? Do you think it is to be handled as an intentional RF transmitter, similarly to an ISM? Let's consider it is not an intentional transmitter, as the emission depends on the broadness of the reference loop, does it make sense to do measurement at three or ten meters? Do you think immunity as well can be anlysed regardless the actual installation? As my field of interest is bounded to electromedical devices and actually I have no garden to take care of, can someone out of there help my friend to send this problem to grass? Thanks in advance. m.p. - ESAOTE S.p.A. Massimo Polignano Research Product DevelopmentDesign Quality Control Mngr Via di Caciolle,15tel:+39.055.4229402 I- 50127 Florence fax:+39.055.4223305 e-mail: massimo.polign...@esaote.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: Conducted Emissions Test in Telephones
Joe and Group, Thanks for your answers. But I think I should refine some points where I still have some doubts. I'll try to put my doubts in topic mode, for a matter of clarity: - The case is this: I have a Telephone Set (wired to the Public Telephony Network). And I'd like to sell it to markets where the EMC laws are mandatory. - What Standards apply for this kind of product?? (FCC XXX, EN XXX)?? - Does this kind of equipment need to be tested for electromagnetic emissions (conducted and radiated)??? Its only supply is the Public Telephony Network, that in Brazil supplies a voltage of 48Vdc. - In the case of MUST BE TESTED for conducted and radiated emissions, how should I realize the test? With the phone in idle mode, in receiving mode, in making call mode??? Or all of the previous modes? Well, it's all for the moment. Thanks in advance for those who help. Best Regards Muriel *** Muriel Bittencourt de Liz - Test Engineer Lab of Applied Electromagnetism for Engineering Dept. of Electrical Engineering Federal University at Santa Catarina State Florianópolis, Santa Catarina State Brazil In a message dated 6/28/01, Geoff Lister writes: EN55022:1998 section 9.5 indicates that measurements must be made on telecommunication ports, and covers, in great detail how this should be done. Hi Muriel: Geoff has provided a succinct answer to the question you posed. I just want to add that you will also have to test for immunity per EN 55024 if you plan to CE mark your product. This standard includes about seven different immunity tests (static discharge, lightning, etc.). Of the tests included in EN 55024, perhaps the most difficult is the conducted immunity test. For this test, common mode RF signals of 3 VRMS, 150 KHz to 80 MHz, are applied to the phone line. The RF carrier is 80% AM modulated at 1 KHz to simulate an AM radio station. Limits are placed on the amount of demodulated 1 KHz that appears on the phone line and in the handset. My experience with this new test suggests that most conventional telephone designs will have difficulty passing. You may need to add some special filtering in strategic locations order to pass. Joe Randolph Telecom Design Consultant Randolph Telecom, Inc. 781-721-2848 http://www.randolph-telecom.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall,
Re: Conducted Emissions Test in Telephones
In a message dated 6/28/01, Geoff Lister writes: EN55022:1998 section 9.5 indicates that measurements must be made on telecommunication ports, and covers, in great detail Hi Muriel: Geoff has provided a succinct answer to the question you posed. I just want to add that you will also have to test for immunity per EN 55024 if you plan to CE mark your product. This standard includes about seven different immunity tests (static discharge, lightning, etc.). Of the tests included in EN 55024, perhaps the most difficult is the conducted immunity test. For this test, common mode RF signals of 3 VRMS, 150 KHz to 80 MHz, are applied to the phone line. The RF carrier is 80% AM modulated at 1 KHz to simulate an AM radio station. Limits are placed on the amount of demodulated 1 KHz that appears on the phone line and in the handset. My experience with this new test suggests that most conventional telephone designs will have difficulty passing. You may need to add some special filtering in strategic locations order to pass. Joe Randolph Telecom Design Consultant Randolph Telecom, Inc. 781-721-2848 http://www.randolph-telecom.com
RE: Conducted Emissions Test in Telephones
Muriel, EN55022:1998 section 9.5 indicates that measurements must be made on telecommunication ports, and covers, in great detail how this should be done. Section 8.2 starts with The operational conditions of the EUT shall be determined by the manufacturer according to the typical use of the EUT with respect to the expected highest level of emission. So, you should check both at standby and active for the highest levels. Other CISPR 22 related specifications may differ, but you will need to test for countries using the EN specs. Best regards, Geoff Lister (geoff.lis...@motion-media.com) Senior Engineer Motion Media Technology Ltd. Horton Hall, Horton, Bristol, BS37 6QN, UK Voice direct +44 (0) 1454 338561 Voice switchboard +44 (0) 1454 313444 Fax +44 (0) 1454 313678 http://www.motion-media.com -Original Message- From: Muriel Bittencourt de Liz [mailto:mur...@eel.ufsc.br] Sent: 27 June 2001 22:57 To: EMC-PSTC List Subject: Conducted Emissions Test in Telephones Hello Group, I'd like to know if telephone devices (plain telephone devices) must be tested for conducted emissions (CISPR 22, Class B). And if they must, what is the proceeding for testing them? Should I test with the telephone in stand-by (no calls) or during a call?? Thanks in advance for the answers. Best Regards Muriel --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall, --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.261 / Virus Database: 131 - Release Date: 06/06/01 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall,
Conducted Emissions Test in Telephones
Hello Group, I'd like to know if telephone devices (plain telephone devices) must be tested for conducted emissions (CISPR 22, Class B). And if they must, what is the proceeding for testing them? Should I test with the telephone in stand-by (no calls) or during a call?? Thanks in advance for the answers. Best Regards Muriel --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall,
Re: EN 55022 Conducted emissions DC
Not a legalese answer but a technical consideration. RE are measured only above 30 MHz due to measurement accuracy concerns at lower frequencies. The CE limit, in addition to preserving power quality in radio frequency bands, also limits RE from long power lines. So there is a good technical reason for imposing the same CE limits on your dc power distribution. If you wanted an algorithm, you could say that you should control CE for the purpose of controlling RE when the power line is a tenth wavelength or longer. This should effectively remove concern at switching frequencies. Also, assuming you are routing feeder and return together, you can limit the control to common mode emissions. -- From: Terry Meck tjm...@accusort.com To: emc-p...@ieee.org Subject: EN 55022 Conducted emissions DC Date: Tue, May 15, 2001, 3:06 PM Hello all, Is there any new requirement on doing conducted emissions testing on distributed DC inside a building. RE: EN 55022:1998 The DC comes from an AC - DC supply (compliant). Would there be a cable length above which the conducted test must be done? I know some immunity tests are required depending in length is this also true of conducted emissions? This has no relationship to Telecom or wires leaving a building. Terry J. Meck Accu-Sort Systems --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall, --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall,
EN 55022 Conducted emissions DC
Hello all, Is there any new requirement on doing conducted emissions testing on distributed DC inside a building. RE: EN 55022:1998 The DC comes from an AC - DC supply (compliant). Would there be a cable length above which the conducted test must be done? I know some immunity tests are required depending in length is this also true of conducted emissions? This has no relationship to Telecom or wires leaving a building. Terry J. Meck Accu-Sort Systems --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall,
Re: Emissions from dithered clocks etc.
200105091432.jaa16...@valencia.rsn.hp.com, Richard A. Schumacher schum...@rsn.hp.com inimitably wrote: A New Work proposal is to be submitted to IEC CISPR/G, concerning any changes to emission standard CISPR22/EN55022 that may need to be made to deal with dithered clocks and similar. It is at an early stage at present, but those concerned should keep a look out for it and decide whether they need to participate in the work at national or international level. Previously, work in UK had suggested that no change was necessary. Some new effect of emissions from dithered clocks may have emerged. Could you elaborate? No, that's all there is. If the New Work is voted positive, CISPR/G will expect contributions to be submitted, describing the nature of the disturbances and proposing limits and perhaps methods of measurement. -- Regards, John Woodgate, OOO - Own Opinions Only. Phone +44 (0)1268 747839 Fax +44 (0)1268 777124. http://www.jmwa.demon.co.uk Why not call a vertically- applied manulo-pedally-operated quasi-planar chernozem-penetrating and excavating implement a SPADE? --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall,
Emissions from dithered clocks etc.
A New Work proposal is to be submitted to IEC CISPR/G, concerning any changes to emission standard CISPR22/EN55022 that may need to be made to deal with dithered clocks and similar. It is at an early stage at present, but those concerned should keep a look out for it and decide whether they need to participate in the work at national or international level. Previously, work in UK had suggested that no change was necessary. Some new effect of emissions from dithered clocks may have emerged. -- Regards, John Woodgate, OOO - Own Opinions Only. Phone +44 (0)1268 747839 Fax +44 (0)1268 777124. http://www.jmwa.demon.co.uk Why not call a vertically- applied manulo-pedally-operated quasi-planar chernozem-penetrating and excavating implement a SPADE? --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall,
Emissions vs Immunity Survey
Thanks to all who responded to my question on Class A Emissions/Class B Immunity. I would like to do a quantitative analysis of the groups opinion on this issue. The follwoing questions require only yes/no answers. Please do not respond to the group. If you would like the results of this survey, please let me know. Responses from European Bodies are greatly appreciated. EN 61326 has the traditional Class A and Class B limits for radiated and line conducted emissions. EN 61326 has several categories of immunity limits. They are as follows: Minimum immunity Industrial immunity Controlled EM environment immunity Portable test and measurement immunity In Europe, is a Class A environment always industrial? In Europe, is there an environment that is Class A, non-industrial, yet powered by a low voltage network that does not supply power to buildings used for domestic purposes? In Europe, are laboratories located in industrial environments or domestic environments? Is it acceptable to test to Class A limits for emissions and the minimum immunity requirements? Thanks in advance for your responses. Regards Joe Martin EMC/Product Safety Engineer Applied Biosystems marti...@appliedbiosystems.com Does Class A non-industrial environment exist? Can you have Class A emissions with minimum immunity requirements? Does Europe have non-industrial low voltage supplies? Is Class A only for industrial environment? --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall,
Re: Radiated Emissions - French Statement
Bonjour de Montréal, Pas de problème... Here is the requested text, but you know you can greatly improve your French while learning a lot in EMC by participating in the next IEEE International Symposium in Montréal. Just follow the link in the trailer of this message. Canada (English) Industry Canada Compliance Statement Remark for the hardware products supported by this guide These digital devices do not exceed the Class B limits for radio noise emission from digital apparatus devices set out in the Radio Interference Regulation of Industry Canada. (Français) Conformité avec les exigences du ministère de l’Industrie Canada Remarque sur les produits matériels couverts par ce guide Ces appareils numériques n’émettent aucun bruit radioélectrique dépassant les limites applicables aux appareils numériques de Classe B prescrites dans le Règlement sur le brouillage radioélectrique édicté par Industrie Canada. Best regards, Benoît Nadeau 3/23/2001 -0500, John Juhasz wrote: Hello all . . . I am looking for the French 'part 15' (ICES-003) statement for radiated emissions compliance. I have the text but my marketing folks are looking for the statement with the accent marks in the appropriate places . . . Perhaps one of our French Canadian colleagues can offer a response? (Perhaps in a MS Word file attachment?. . . not sure if the characters will map properly in the body of an e-mail message) John Juhasz Fiber Options Bohemia, NY -- Benoît Nadeau, ing. M.ing (P.eng., M.eng.) Conformity Group Manager Matrox 1055, boul. St-Regis Dorval (Québec) Canada H9P 2T4 Tel: (514) 822-6000 (x2475) Fax: (514) 822-6275 http://www.matrox.com Chairman 2001 IEEE EMC International Symposium on Electromagnetic Compatibility Montreal August 13 to 17, 2001 http://www.2001emcmtl.org --
CPU clock emissions
Hi group, It's Friday and thinking hurts the head on a Friday, so I'll take the easier option and just ask. I have just returned from emissions testing on a new product. The product uses a DSP which runs off an 8Mhz oscillator and internally 'ups' this to 40Mhz. It also has a CLOCK_OUT pin which is currently floating. I have 'beyond the limit' emissions at 40Mhz and higher harmonics of this frequency. Has anyone got any good simple, cost effective ideas how to suppress these emissions which are apparent in both radiated and conducted emissions? Would appreciate your personal experiences on suppressing these narrowband emissions are welcome. Regards - Chris Chileshe - Ultronics Ltd This message has been checked for all known viruses, by Star Internet, delivered through the MessageLabs Virus Control Centre. For further information visit: http://www.star.net.uk/stats.asp --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on Virtual Conference Hall,
Lithuanian emissions restrictions?
Is anyone familiar with limits to operating frequencies for ISM equipment in Lithuania? I've checked http://www.radio.lt/frequency_table.htm and I note several bands (6MHz) _reserved_ for use by ISM, but are there any corresponding prohibitions for ISM operation? My induction heating equipment operates from 50 to 500 kHz. Links, speculations, anecdotes welcome... Thanks --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Doubt with conducted emissions measurement
Well, the original comment was that a LISN is a better spec'd source impedance than a feedthrough capacitor and current probe. The feedthrough cap is spec'd as a Bode plot of insertion loss between a 50 Ohm source and load in SAE ARP 936 (I think that's the right number). The impedance added by the current probe is negligible. It is the current probe transfer impedance divided by the square of the turns ratio. This is in all cases of measurement probes much less than one Ohm. I would agree that regardless of feedthrough cap or current probe, having a variable length conductor between EUT and impedance stabilization point introduces variability. But the solution for this is the same regardless of the type of impedance stabilization - keep the line length short relative to a wavelength. -- From: Brent G DeWitt bdew...@ix.netcom.com To: 'Ken Javor' ken.ja...@emccompliance.com, 'praveen rao' p...@tennyson.com.au, 'muriel bittencourt de liz' mur...@grucad.ufsc.br Cc: emc-p...@majordomo.ieee.org Subject: RE: Doubt with conducted emissions measurement Date: Thu, Dec 28, 2000, 6:27 PM Hi Ken, Ok, you caught me exercising a pet peeve (hop up here on the table peeve). My problem stems from specifications which state nominal component values rather than a verifiable Zin. The 61000-4-4 mains coupler is a pretty worst case example. Huge variation in the actual devices from manufacturer to manufacturer. The thing I like better about the LISN is that both the insertion loss and Zin as a measurement system component are specified and verifiable. Of course, connections to the LISN can seriously distort it's response, just as can connections to the 10 uF cap. I hope my personal prejudices don't step on anyone's toes. Best regards, Brent -Original Message- From: Ken Javor [mailto:ken.ja...@emccompliance.com] Sent: Wednesday, December 27, 2000 12:57 AM To: bdew...@ix.netcom.com; 'praveen rao'; 'muriel bittencourt de liz' Cc: emc-p...@majordomo.ieee.org Subject: Re: Doubt with conducted emissions measurement Hi Brent, Specifically NOT meaning to argue, but only in pursuit of the TRUTH, isn't the 10 uF feedthrough cap a perfectly well-defined source impedance above, say 15/20 kHz, where the old MIL-STD-461A/B/C CE03 limit started? Which is not to say that the current measurement is preferred, but what makes a LISN more consistent? The new MIL-STD-462D and -461E cites the fact that a LISN is more representative of a real world bus impedance, and therefore a filter designed to work with a LISN works similarly with the real bus. But that is not a testability issue at all. Respectfully, Ken Javor -- From: Brent G DeWitt bdew...@ix.netcom.com To: 'Ken Javor' ken.ja...@emccompliance.com, 'Praveen Rao' p...@tennyson.com.au, 'Muriel Bittencourt de Liz' mur...@grucad.ufsc.br Cc: emc-p...@majordomo.ieee.org Subject: RE: Doubt with conducted emissions measurement Date: Tue, Dec 26, 2000, 11:48 PM Hi Ken, After twenty years or so of EMC testing, I find myself more often using the word consistent rather than accurate. This is exactly the issue of n ohm LISNs versus voltage or current probes. Current probes and voltage probes are certainly as accurate as a LISN, but they leave in doubt what source impedance the system was working into. The selection of 50 ohms is certainly debatable, especially in light of the 150 ohm specification for CDNs, and I won't even attempt to defend the number. The key is that, when we can't hope to define what's right, we can at least attempt to define consistency. Best regards sir, Brent DeWitt -Original Message- From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf Of Ken Javor Sent: Tuesday, December 26, 2000 7:56 PM To: Praveen Rao; 'Muriel Bittencourt de Liz' Cc: emc-p...@majordomo.ieee.org Subject: Re: Doubt with conducted emissions measurement 2) Why does Mr., Rao (or anyone else) feel that the LISN-based measurement is more accurate than a current probe measurement? I can see pros and cons to each, myself. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: Doubt with conducted emissions measurement
Hi Ken, Ok, you caught me exercising a pet peeve (hop up here on the table peeve). My problem stems from specifications which state nominal component values rather than a verifiable Zin. The 61000-4-4 mains coupler is a pretty worst case example. Huge variation in the actual devices from manufacturer to manufacturer. The thing I like better about the LISN is that both the insertion loss and Zin as a measurement system component are specified and verifiable. Of course, connections to the LISN can seriously distort it's response, just as can connections to the 10 uF cap. I hope my personal prejudices don't step on anyone's toes. Best regards, Brent -Original Message- From: Ken Javor [mailto:ken.ja...@emccompliance.com] Sent: Wednesday, December 27, 2000 12:57 AM To: bdew...@ix.netcom.com; 'praveen rao'; 'muriel bittencourt de liz' Cc: emc-p...@majordomo.ieee.org Subject: Re: Doubt with conducted emissions measurement Hi Brent, Specifically NOT meaning to argue, but only in pursuit of the TRUTH, isn't the 10 uF feedthrough cap a perfectly well-defined source impedance above, say 15/20 kHz, where the old MIL-STD-461A/B/C CE03 limit started? Which is not to say that the current measurement is preferred, but what makes a LISN more consistent? The new MIL-STD-462D and -461E cites the fact that a LISN is more representative of a real world bus impedance, and therefore a filter designed to work with a LISN works similarly with the real bus. But that is not a testability issue at all. Respectfully, Ken Javor -- From: Brent G DeWitt bdew...@ix.netcom.com To: 'Ken Javor' ken.ja...@emccompliance.com, 'Praveen Rao' p...@tennyson.com.au, 'Muriel Bittencourt de Liz' mur...@grucad.ufsc.br Cc: emc-p...@majordomo.ieee.org Subject: RE: Doubt with conducted emissions measurement Date: Tue, Dec 26, 2000, 11:48 PM Hi Ken, After twenty years or so of EMC testing, I find myself more often using the word consistent rather than accurate. This is exactly the issue of n ohm LISNs versus voltage or current probes. Current probes and voltage probes are certainly as accurate as a LISN, but they leave in doubt what source impedance the system was working into. The selection of 50 ohms is certainly debatable, especially in light of the 150 ohm specification for CDNs, and I won't even attempt to defend the number. The key is that, when we can't hope to define what's right, we can at least attempt to define consistency. Best regards sir, Brent DeWitt -Original Message- From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf Of Ken Javor Sent: Tuesday, December 26, 2000 7:56 PM To: Praveen Rao; 'Muriel Bittencourt de Liz' Cc: emc-p...@majordomo.ieee.org Subject: Re: Doubt with conducted emissions measurement 2) Why does Mr., Rao (or anyone else) feel that the LISN-based measurement is more accurate than a current probe measurement? I can see pros and cons to each, myself. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Doubt with conducted emissions measurement
Hi Brent, Specifically NOT meaning to argue, but only in pursuit of the TRUTH, isn't the 10 uF feedthrough cap a perfectly well-defined source impedance above, say 15/20 kHz, where the old MIL-STD-461A/B/C CE03 limit started? Which is not to say that the current measurement is preferred, but what makes a LISN more consistent? The new MIL-STD-462D and -461E cites the fact that a LISN is more representative of a real world bus impedance, and therefore a filter designed to work with a LISN works similarly with the real bus. But that is not a testability issue at all. Respectfully, Ken Javor -- From: Brent G DeWitt bdew...@ix.netcom.com To: 'Ken Javor' ken.ja...@emccompliance.com, 'Praveen Rao' p...@tennyson.com.au, 'Muriel Bittencourt de Liz' mur...@grucad.ufsc.br Cc: emc-p...@majordomo.ieee.org Subject: RE: Doubt with conducted emissions measurement Date: Tue, Dec 26, 2000, 11:48 PM Hi Ken, After twenty years or so of EMC testing, I find myself more often using the word consistent rather than accurate. This is exactly the issue of n ohm LISNs versus voltage or current probes. Current probes and voltage probes are certainly as accurate as a LISN, but they leave in doubt what source impedance the system was working into. The selection of 50 ohms is certainly debatable, especially in light of the 150 ohm specification for CDNs, and I won't even attempt to defend the number. The key is that, when we can't hope to define what's right, we can at least attempt to define consistency. Best regards sir, Brent DeWitt -Original Message- From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf Of Ken Javor Sent: Tuesday, December 26, 2000 7:56 PM To: Praveen Rao; 'Muriel Bittencourt de Liz' Cc: emc-p...@majordomo.ieee.org Subject: Re: Doubt with conducted emissions measurement 2) Why does Mr., Rao (or anyone else) feel that the LISN-based measurement is more accurate than a current probe measurement? I can see pros and cons to each, myself. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: Doubt with conducted emissions measurement
Hi Ken, After twenty years or so of EMC testing, I find myself more often using the word consistent rather than accurate. This is exactly the issue of n ohm LISNs versus voltage or current probes. Current probes and voltage probes are certainly as accurate as a LISN, but they leave in doubt what source impedance the system was working into. The selection of 50 ohms is certainly debatable, especially in light of the 150 ohm specification for CDNs, and I won't even attempt to defend the number. The key is that, when we can't hope to define what's right, we can at least attempt to define consistency. Best regards sir, Brent DeWitt -Original Message- From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf Of Ken Javor Sent: Tuesday, December 26, 2000 7:56 PM To: Praveen Rao; 'Muriel Bittencourt de Liz' Cc: emc-p...@majordomo.ieee.org Subject: Re: Doubt with conducted emissions measurement 2) Why does Mr., Rao (or anyone else) feel that the LISN-based measurement is more accurate than a current probe measurement? I can see pros and cons to each, myself. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Doubt with conducted emissions measurement
I disagree with a few statements made herein. Some differences are factual, but I am interested in general response on my last issue. 1) The military discarded the 5 uH LISN a long time ago. Commercial aerospace still uses it. In 1993 military adopted 50 uH LISN, essentially same as CISPR. 2) Why does Mr., Rao (or anyone else) feel that the LISN-based measurement is more accurate than a current probe measurement? I can see pros and cons to each, myself. -- From: Praveen Rao p...@tennyson.com.au To: 'Muriel Bittencourt de Liz' mur...@grucad.ufsc.br Cc: emc-p...@majordomo.ieee.org Subject: RE: Doubt with conducted emissions measurement Date: Tue, Dec 26, 2000, 5:26 PM Hi Muriel and group, Hope you all had a good Christmas. Yes, As Chris mentions, there can be problems with coupling/de-coupling networks. A classic example is the T-ISNs for conducted emissions on telecommunication lines as per the new EN55022 : 1998 The mains LISN however causing problems is not that common. For Mil Stds tests current probes are normally used, but only for a few type of tests (like DC and other leads), where the de-coupling device is still a LISN or a 10 micro Farad feed through Capacitor. Mains supply units are still tested with LISNs. But these are 5 micro henry LISNs. And the test set ups are quite different. The LISN tests are more reliable and repeatable than the current probe tests. Happy New Year. The real new Millenium. Praveen rao -Original Message- From: Muriel Bittencourt de Liz [mailto:mur...@grucad.ufsc.br] Sent: Saturday, 23 December 2000 3:05 AM To: Lista de EMC da IEEE Subject: Doubt with conducted emissions measurement Hello Group! First of all, I wish a merry christmas and a happy new year for the list members. Second, I'd like to solve a doubt. It concerns the methodology of conducted emissions tests. Let's suppose a power electronic equipment (static converter) that has a boost converter in the entrance that's used for power factor correction (PFC). When I make a conducted emissions test, I plug the converter in a LISN, then I plug the LISN in the outlet, this way (the classical way): Equipment = LISN = Outlet (Mains) Well, the LISN consists of a RLC network that has the purposes of: - prevent that external interference from the mains contaminate the measurement - create a stabilized impedance (50 ohms) in the frequency range of interest (150kHz-30MHz) to make results repeatable, from site to site. Ok, what I've said until here is well known and is present in every book about this subject of EMC. My doubt is this: The LISN can't interfere in the functional operation of the converter? Things like resonance, extra ripple can't occur? And, imagining the worst scenario, can the LISN make my equipment not work according to what's expected? Another thing I was thinking about is the fact that the military tests os conducted emissions are done with a probe, and not using a LISN. I'm very curious about this subject because I was asked about this question and I became very surprised, because I have never thought about this. We are, generally, so interested in results that we forget to ask the basic questions sometimes. Well, I think that's all. Thanks in advance for those who can help me. Best Regards Eng. Muriel Bittencourt de Liz EMC Testing and Troubleshooting Group of Conception and Analysis of Electromagnetic Devices Federal University at Santa Catarina Florianópolis, SC, Brazil --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac
RE: Doubt with conducted emissions measurement
Hi Muriel and group, Hope you all had a good Christmas. Yes, As Chris mentions, there can be problems with coupling/de-coupling networks. A classic example is the T-ISNs for conducted emissions on telecommunication lines as per the new EN55022 : 1998 The mains LISN however causing problems is not that common. For Mil Stds tests current probes are normally used, but only for a few type of tests (like DC and other leads), where the de-coupling device is still a LISN or a 10 micro Farad feed through Capacitor. Mains supply units are still tested with LISNs. But these are 5 micro henry LISNs. And the test set ups are quite different. The LISN tests are more reliable and repeatable than the current probe tests. Happy New Year. The real new Millenium. Praveen rao -Original Message- From: Muriel Bittencourt de Liz [mailto:mur...@grucad.ufsc.br] Sent: Saturday, 23 December 2000 3:05 AM To: Lista de EMC da IEEE Subject: Doubt with conducted emissions measurement Hello Group! First of all, I wish a merry christmas and a happy new year for the list members. Second, I'd like to solve a doubt. It concerns the methodology of conducted emissions tests. Let's suppose a power electronic equipment (static converter) that has a boost converter in the entrance that's used for power factor correction (PFC). When I make a conducted emissions test, I plug the converter in a LISN, then I plug the LISN in the outlet, this way (the classical way): Equipment = LISN = Outlet (Mains) Well, the LISN consists of a RLC network that has the purposes of: - prevent that external interference from the mains contaminate the measurement - create a stabilized impedance (50 ohms) in the frequency range of interest (150kHz-30MHz) to make results repeatable, from site to site. Ok, what I've said until here is well known and is present in every book about this subject of EMC. My doubt is this: The LISN can't interfere in the functional operation of the converter? Things like resonance, extra ripple can't occur? And, imagining the worst scenario, can the LISN make my equipment not work according to what's expected? Another thing I was thinking about is the fact that the military tests os conducted emissions are done with a probe, and not using a LISN. I'm very curious about this subject because I was asked about this question and I became very surprised, because I have never thought about this. We are, generally, so interested in results that we forget to ask the basic questions sometimes. Well, I think that's all. Thanks in advance for those who can help me. Best Regards Eng. Muriel Bittencourt de Liz EMC Testing and Troubleshooting Group of Conception and Analysis of Electromagnetic Devices Federal University at Santa Catarina Florianópolis, SC, Brazil --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: Doubt with conducted emissions measurement
-Original Message- From: Muriel Bittencourt de Liz [mailto:mur...@grucad.ufsc.br] Sent: Friday, December 22, 2000 8:05 AM To: Lista de EMC da IEEE Subject: Doubt with conducted emissions measurement Hello Group! First of all, I wish a merry christmas and a happy new year for the list members. Second, I'd like to solve a doubt. It concerns the methodology of conducted emissions tests. Let's suppose a power electronic equipment (static converter) that has a boost converter in the entrance that's used for power factor correction (PFC). When I make a conducted emissions test, I plug the converter in a LISN, then I plug the LISN in the outlet, this way (the classical way): Equipment = LISN = Outlet (Mains) Well, the LISN consists of a RLC network that has the purposes of: - prevent that external interference from the mains contaminate the measurement - create a stabilized impedance (50 ohms) in the frequency range of interest (150kHz-30MHz) to make results repeatable, from site to site. Ok, what I've said until here is well known and is present in every book about this subject of EMC. My doubt is this: The LISN can't interfere in the functional operation of the converter? Things like resonance, extra ripple can't occur? And, imagining the worst scenario, can the LISN make my equipment not work according to what's expected? Another thing I was thinking about is the fact that the military tests os conducted emissions are done with a probe, and not using a LISN. I'm very curious about this subject because I was asked about this question and I became very surprised, because I have never thought about this. We are, generally, so interested in results that we forget to ask the basic questions sometimes. Well, I think that's all. Thanks in advance for those who can help me. Best Regards Eng. Muriel Bittencourt de Liz EMC Testing and Troubleshooting Group of Conception and Analysis of Electromagnetic Devices Federal University at Santa Catarina Florianópolis, SC, Brazil Muriel: The LISN adds only modest (although standardized) amounts of inductance and capacitance to the powerline. Typically, the LISN has a series inductor of only 5 to 50 microhenries, and on the power source side, a .1 to 10 microfarad capacitor. The insertion of the LISN into the powerline should not be electrically significant. OTOH, it certainly is possible to imagine some scenario where the EUT interacts with the specific circuit values of the LISN. However, any EUT which did that would probably be a very unique gadget, and it probably would encounter problems plugging into random outlets. Regarding mil testing; Mil-Std-462D specifies an LISN for both Methods CE101 and CE102. For CE101, the noise current into the LISN is measured by a current probe around the EUT powerline. For CE102, the analyzer is connected to the LISN signal output port to read noise voltage across the LISN impedance. The British Def Stan 59-41 Method DCE01 also uses the LISN and current probe technique. Regards, Ed Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA. USA 858-505-2780 (Voice) 858-505-1583 (Fax) Military Avionics EMC Services Is Our Specialty Shake-Bake-Shock - Metrology - Reliability Analysis --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: Doubt with conducted emissions measurement
Muriel, Coupling/Decoupling networks (of which LISN's are a subgroup) can affect DUT performance. I myself have not experienced this with a conducted emissions LISN, but I have experienced it with an EFT generator. We made a product that had an internal thermal printer. We EFT test in house. Part of my EFT testing included verifying the operation of this printer during the EFT threat. During testing, it seemed as though the printer was failing. I would start the test, try to access the printer and be denied. However, the second time I accessed the printer (and any time thereafter) I would be allowed access and the unit would print fine. I thought it was an EFT failure. However, if I left my product connected to the EFT generator with the EFT turned off, its printer would show the same problem. Why? The EFT generator has a coupling/decoupling network with some huge in-line inductors and some capacitors to ground. I did some probing around with an oscilloscope and found that the first time I accessed the printer, my product would draw a large, instantaneous current which charged up the capacitors in the printer's power supply. The second time I accessed the printer, the caps were already charged and this instantaeous current wasn't needed. This initial current draw was being limited by the in-line inductors in the EFT generator. As such, the power supply voltages in my DUT were sagging while they were waiting for the required current. During this voltage sag, my printer logic was getting locked up. So, any coupling/decoupling network with in-line inductors (which include LISN's) can and will limit instantaneous current changes to the products connected to them. If your product depends upon these currents to maintain regulation of its power supplies, then the product may experience difficulties. Happy Holidays! Chris -Original Message- From: Muriel Bittencourt de Liz [SMTP:mur...@grucad.ufsc.br] Sent: Friday, December 22, 2000 11:05 AM To: Lista de EMC da IEEE Subject: Doubt with conducted emissions measurement Hello Group! First of all, I wish a merry christmas and a happy new year for the list members. Second, I'd like to solve a doubt. It concerns the methodology of conducted emissions tests. Let's suppose a power electronic equipment (static converter) that has a boost converter in the entrance that's used for power factor correction (PFC). When I make a conducted emissions test, I plug the converter in a LISN, then I plug the LISN in the outlet, this way (the classical way): Equipment = LISN = Outlet (Mains) Well, the LISN consists of a RLC network that has the purposes of: - prevent that external interference from the mains contaminate the measurement - create a stabilized impedance (50 ohms) in the frequency range of interest (150kHz-30MHz) to make results repeatable, from site to site. Ok, what I've said until here is well known and is present in every book about this subject of EMC. My doubt is this: The LISN can't interfere in the functional operation of the converter? Things like resonance, extra ripple can't occur? And, imagining the worst scenario, can the LISN make my equipment not work according to what's expected? Another thing I was thinking about is the fact that the military tests os conducted emissions are done with a probe, and not using a LISN. I'm very curious about this subject because I was asked about this question and I became very surprised, because I have never thought about this. We are, generally, so interested in results that we forget to ask the basic questions sometimes. Well, I think that's all. Thanks in advance for those who can help me. Best Regards Eng. Muriel Bittencourt de Liz EMC Testing and Troubleshooting Group of Conception and Analysis of Electromagnetic Devices Federal University at Santa Catarina Florianópolis, SC, Brazil --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail
RE: Doubt with conducted emissions measurement
Muriel, this is a very question, and I'll let better qualified people answer your specific concerns. Now, if I may add my 2 cents worth of experience in a 'similar' situation that involved conducted emission on SIGNAL leads: Under certain conditions, when the required CDN does interfere with signal template (such as T1) and affected equipment functionality, we used a current clamp. The danger of those networks interfering with the measurement/s equipment exists and the test personnel should be aware of it. Season Greetings to all from (already) white Ottawa. Regards, Naftali Shani, Catena Networks (www.catena.com) 307 Legget Drive, Kanata, Ontario, Canada K2K 3C8 Voice +1.613.599.6430 X.8277 Fax +1.613.599.6433 E-mail: nsh...@catena.com or n...@ieee.org -Original Message- From: Muriel Bittencourt de Liz [mailto:mur...@grucad.ufsc.br] Sent: Friday, December 22, 2000 11:05 AM To: Lista de EMC da IEEE Subject:Doubt with conducted emissions measurement Hello Group! First of all, I wish a merry christmas and a happy new year for the list members. Second, I'd like to solve a doubt. It concerns the methodology of conducted emissions tests. Let's suppose a power electronic equipment (static converter) that has a boost converter in the entrance that's used for power factor correction (PFC). When I make a conducted emissions test, I plug the converter in a LISN, then I plug the LISN in the outlet, this way (the classical way): Equipment = LISN = Outlet (Mains) Well, the LISN consists of a RLC network that has the purposes of: - prevent that external interference from the mains contaminate the measurement - create a stabilized impedance (50 ohms) in the frequency range of interest (150kHz-30MHz) to make results repeatable, from site to site. Ok, what I've said until here is well known and is present in every book about this subject of EMC. My doubt is this: The LISN can't interfere in the functional operation of the converter? Things like resonance, extra ripple can't occur? And, imagining the worst scenario, can the LISN make my equipment not work according to what's expected? Another thing I was thinking about is the fact that the military tests os conducted emissions are done with a probe, and not using a LISN. I'm very curious about this subject because I was asked about this question and I became very surprised, because I have never thought about this. We are, generally, so interested in results that we forget to ask the basic questions sometimes. Well, I think that's all. Thanks in advance for those who can help me. Best Regards Eng. Muriel Bittencourt de Liz EMC Testing and Troubleshooting Group of Conception and Analysis of Electromagnetic Devices Federal University at Santa Catarina Florianópolis, SC, Brazil --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Doubt with conducted emissions measurement
Muriel, 1) Your equipment must be designed to operate from the LISN. It must not resonate, generate extra ripple, etc. The concept is that EUT sees a low enough source impedance when connected to any real power distribution system that it operates in a STABLE mode. That means your input filter supplies enough local energy storage such that the EUT requires only power-line frequency replenishment from the mains. 2) The military did use feedthrough capacitors and current probes from 1967 - 1993 to stabilize and measure current conducted emissions. Since '93, they have gone back to LISNs. And a lot of MIL power supply manufacturers complained that power supplies designed to operate off the feedthrough capacitors went unstable when drawing power from LISNs. They had to redesign their input filters. Merry Christmas to all! Ken -- From: Muriel Bittencourt de Liz mur...@grucad.ufsc.br To: Lista de EMC da IEEE emc-p...@ieee.org Subject: Doubt with conducted emissions measurement Date: Fri, Dec 22, 2000, 10:05 AM Hello Group! First of all, I wish a merry christmas and a happy new year for the list members. Second, I'd like to solve a doubt. It concerns the methodology of conducted emissions tests. Let's suppose a power electronic equipment (static converter) that has a boost converter in the entrance that's used for power factor correction (PFC). When I make a conducted emissions test, I plug the converter in a LISN, then I plug the LISN in the outlet, this way (the classical way): Equipment = LISN = Outlet (Mains) Well, the LISN consists of a RLC network that has the purposes of: - prevent that external interference from the mains contaminate the measurement - create a stabilized impedance (50 ohms) in the frequency range of interest (150kHz-30MHz) to make results repeatable, from site to site. Ok, what I've said until here is well known and is present in every book about this subject of EMC. My doubt is this: The LISN can't interfere in the functional operation of the converter? Things like resonance, extra ripple can't occur? And, imagining the worst scenario, can the LISN make my equipment not work according to what's expected? Another thing I was thinking about is the fact that the military tests os conducted emissions are done with a probe, and not using a LISN. I'm very curious about this subject because I was asked about this question and I became very surprised, because I have never thought about this. We are, generally, so interested in results that we forget to ask the basic questions sometimes. Well, I think that's all. Thanks in advance for those who can help me. Best Regards Eng. Muriel Bittencourt de Liz EMC Testing and Troubleshooting Group of Conception and Analysis of Electromagnetic Devices Federal University at Santa Catarina Florianópolis, SC, Brazil --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Doubt with conducted emissions measurement
Hello Group! First of all, I wish a merry christmas and a happy new year for the list members. Second, I'd like to solve a doubt. It concerns the methodology of conducted emissions tests. Let's suppose a power electronic equipment (static converter) that has a boost converter in the entrance that's used for power factor correction (PFC). When I make a conducted emissions test, I plug the converter in a LISN, then I plug the LISN in the outlet, this way (the classical way): Equipment = LISN = Outlet (Mains) Well, the LISN consists of a RLC network that has the purposes of: - prevent that external interference from the mains contaminate the measurement - create a stabilized impedance (50 ohms) in the frequency range of interest (150kHz-30MHz) to make results repeatable, from site to site. Ok, what I've said until here is well known and is present in every book about this subject of EMC. My doubt is this: The LISN can't interfere in the functional operation of the converter? Things like resonance, extra ripple can't occur? And, imagining the worst scenario, can the LISN make my equipment not work according to what's expected? Another thing I was thinking about is the fact that the military tests os conducted emissions are done with a probe, and not using a LISN. I'm very curious about this subject because I was asked about this question and I became very surprised, because I have never thought about this. We are, generally, so interested in results that we forget to ask the basic questions sometimes. Well, I think that's all. Thanks in advance for those who can help me. Best Regards Eng. Muriel Bittencourt de Liz EMC Testing and Troubleshooting Group of Conception and Analysis of Electromagnetic Devices Federal University at Santa Catarina Florianópolis, SC, Brazil --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
FCC Part 18: Conducted emissions frequency range versus LISN performance
I'll be testing a product to FCC Part 18 for the first time, and I'm trying to familiarize myself with the limits in this requirement. In section 18.307(a), conducted emissions limits are specified for ultrasonic equipment. They start at 10kHz, and stop at 30MHz. Yet the measurement procedure specified in section 18.311 (MP-5) gives a graph of LISN performance that only goes down to 150kHz. Am I missing something, or is this the way the regulations read? Patrick Lawler plaw...@west.net --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Auxiliary DC output and Conducted Emissions
Esteemed colleges, I have a question pertaining to conducted emissions performed on a port that is exclusively for the purpose of powering an auxiliary device that we do not manufacture. Our equipment is portable test equipment. This port will supply 28VDC at 1.5A to a piece of equipment the end user will provide, the port itself is provided as convenience to the consumer for equipment they intend to run with our equipment. The equipment is intended to comply with EN 61326 Emissions:CISPR 11, Class B. I am aware of some Immunity testing that is required for Auxiliary Equipment, but is there a perceived requirement for performing Conducted Emissions on this DC output port? My understanding is that since this port is not classified as a Mains input/output, it does not need to comply to a conducted emissions spec. Am I right in this understanding? Thanx for any or all input on this peculiar problem of mine. Douglas Best Compliance Technician IFR America's Inc.Design Engineering ETM Division Tel : +1 316 529 5327 10200 W. York St. FAX : +1 316 522 3676 Wichita Ks, 67215 e-mail: doug.b...@ifrsys.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: ITE Emissions above 1 GHz
Dick, The standard ETS 300-683 is for Radio Equipment used in short range. Is the unit described by Richard falls under this category? Richard, A question raised by you about how to regulate ITE (Information Technology Equipment) device in compliance with Telecom standards is of very important and practical interest. Telecom industry is developing so fast that many other equipment which fall under categories of ITE or Test equipment are involved in the Telecom environment. ... If customers in Telecom industry really want us to test devices of other categories in compliance with Telecom standards, should we raise our price for the extra cost? :-) Barry - On Thu, 16 November 2000, Dick Grobner wrote: Short range device? Look at ETSI 300-683, EMC Std for Short Range Devices - operating freq. 9kHz to 25GHz. Chapter 8 deals with emissions. Hope this helps! -Original Message- From: wo...@sensormatic.com [mailto:wo...@sensormatic.com] Sent: Wednesday, November 15, 2000 3:10 PM To: emc-p...@majordomo.ieee.org Subject: ITE Emissions above 1 GHz I have an Information Technology device that intentionally generates and uses 2.45 GHz signals. EN55022 does not provide limits above 1 GHz. Is there another harmonized EN that can be applied for spurious emissions above 1 GHz? If not, will this product have to be submitted to a Competent Body? Richard Woods --- Thanks. Best Regards, Barry Mab...@anritsu.com ANRITSUwww.anritsu.com Morgan Hill, CA 95037 Tel. 408-778-2000 x 4465 ___ Free Unlimited Internet Access! Try it now! http://www.zdnet.com/downloads/altavista/index.html ___ --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: ITE Emissions above 1 GHz
Short range device? Look at ETSI 300-683, EMC Std for Short Range Devices - operating freq. 9kHz to 25GHz. Chapter 8 deals with emissions. Hope this helps! -Original Message- From: wo...@sensormatic.com [mailto:wo...@sensormatic.com] Sent: Wednesday, November 15, 2000 3:10 PM To: emc-p...@majordomo.ieee.org Subject: ITE Emissions above 1 GHz I have an Information Technology device that intentionally generates and uses 2.45 GHz signals. EN55022 does not provide limits above 1 GHz. Is there another harmonized EN that can be applied for spurious emissions above 1 GHz? If not, will this product have to be submitted to a Competent Body? Richard Woods --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Spurious Emissions above 1 GHz
I am going to ask my previous question in a different (and, hopefully, improved) way. Assume I have an ITE device that is an unintentional radiator (i.e., it is not a transmitter). Also assume the device has spurious emissions above 1 GHz that may not be insignificant. In order to comply with the essential requirements of the EMC Directive, is it sufficient to comply with EN 55022 which has no requirements above 1 GHz? If not, then a relevant harmonized standard must be applied for the emissions above 1 GHz or the TCF route must be followed. Is there a harmonized standard that may be applied to ITE for emissions for above 1 GHz? Richard Woods --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Vedr.: ITE Emissions above 1 GHz
Hello Richard, Is the device a blue tooth using wireless radiation to communicate with other devices, if yes the device is a subjet for the RTTE directive. You may use the ETSI standards: EN 301 489-3 V1.2.1 (2000-08) Electromagnetic compatibility and Radio spectrum Matters (ERM); ElectroMagnetic Compatibility (EMC) standard for radio equipment and services; Part 3: Specific conditions for Short-Range Devices (SRD) operating on frequencies between 9 kHz and 40 GHz and EN 300 440-2 V1.1.1 (2000-07) Electromagnetic compatibility and Radio spectrum Matters (ERM); Short range devices; Radio equipment to be used in the 1 GHz to 40 GHz frequency range; Part 2: Harmonized EN under article 3.2 of the RTTE Directive Those standards may be downloaded free of charge from www.etsi.org. NOTE:They are not harmonized yet! If it not is used for wireless communication then the EN 55022 still shall be used for showing complience with the EMC Directive. Best regards Helge Knudsen Delta Electronics Testing, EMC Venlighedsvej 4, DK-2970 Hoersholm Telephone : +45 45 86 77 22 Fax : +45 45 86 58 98 wo...@sensormatic.com 15-11-00 22:10 I have an Information Technology device that intentionally generates and uses 2.45 GHz signals. EN55022 does not provide limits above 1 GHz. Is there another harmonized EN that can be applied for spurious emissions above 1 GHz? If not, will this product have to be submitted to a Competent Body? Richard Woods --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
ITE Emissions above 1 GHz
I have an Information Technology device that intentionally generates and uses 2.45 GHz signals. EN55022 does not provide limits above 1 GHz. Is there another harmonized EN that can be applied for spurious emissions above 1 GHz? If not, will this product have to be submitted to a Competent Body? Richard Woods --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Spurious Emissions Test up to 220GHz
Just curious: Isn't there some upper frequency cut-off here, regardless of where a fifth harmonic falls? What radio link would be disturbed at 220 GHz? -- From: Leslie Bai leslie_...@yahoo.com To: emc-p...@ieee.org Subject: Spurious Emissions Test up to 220GHz Date: Thu, Nov 2, 2000, 6:10 PM Hello, Group, Is there any lab who can test radiated spurious emissions up to 220GHz (5th harmonics of radio operating at 38GHz)? Is there any supplier who can provide pre-amplifier(s) and harmonics mixer(s) up to 220GHz for this measurement (I already have all antennae up to 220GHz)? Thanks, Leslie __ Do You Yahoo!? From homework help to love advice, Yahoo! Experts has your answer. http://experts.yahoo.com/ --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Spurious Emissions Test up to 220GHz
Hello, Group, Is there any lab who can test radiated spurious emissions up to 220GHz (5th harmonics of radio operating at 38GHz)? Is there any supplier who can provide pre-amplifier(s) and harmonics mixer(s) up to 220GHz for this measurement (I already have all antennae up to 220GHz)? Thanks, Leslie __ Do You Yahoo!? From homework help to love advice, Yahoo! Experts has your answer. http://experts.yahoo.com/ --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Conducted Emissions
Forwarded for John --mg Group, We are engaged in re-arranging our conformance lab and are looking to save space by permanently installing the 50m of cable used to connect our EUT (motor drive) to its load (a 3phase motor and load). I have a couple of questions: Is the capacity of the cable critical to the test or can we lay out the largest cable necessary (120mm2 screened) and use this regardless of the rating required for the load? The cable is planned to terminate in a patch panel at both ends so that links can be made to a variety of EUT and load rigs. How critical to the validity of the test is the position of the cable with respect to the ground plane. We plan to route the cable in the ceiling void on a cable tray which will be boded to ground. Best Regards John Richards Customer Assurance Engineer Eurotherm Drives Ltd +44 (0)1903 737294 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: AS/NZS 3548 - conducted emissions on telecom ports?
David, I do not believe you have had anyone answer your question to the group. Sorry I have been away from the office a lot lately. Australia has not yet adopted the 1998 version of CISPR 22 or EN 55022. As you are probably aware, the latest version of AS/NZS 3548 is 1995. We will be commencing work shortly on updating AS/NZS 3548 to align with the latest version etc of CISPR etc. It is therefore not likely this will be completed year. At this time it is not clear if the conducted emissions requirements on telecom ports will be included in the new version or not. Best regards, Kevin Richardson Stanimore Pty Limited Compliance Advice Solutions for Technology Products and Services (Legislation/Regulations/Standards) Ph: 02-4329-4070 (Int'l: +61-2-4329-4070) Fax: 02-4328-5639 (Int'l: +61-2-4328-5639) Mobile: 04-1224-1620 (Int'l: +61-4-1224-1620) Email:k...@compuserve.com kevin.richard...@ieee.org k...@technologist.com (alternate internet) -Original Message- From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf Of David Gelfand Sent: Tuesday, 19 September 2000 5:40 AM To: emc-p...@ieee.org Subject: AS/NZS 3548 - conducted emissions on telecom ports? Hello group, Does Australia implement (or plan to implement) limits for conducted emissions on telecom ports as in EN 55022:1998? Also, who makes T-LISNs for these tests? Thanks, David. David Gelfand Regulatory Approvals Memotec Communications Inc. Montreal Canada --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Harmonic emissions
I am just rejoining the forum after a few weeks absence for vacation and server/domain changes. Early in September it appeared that the harmonic emissions standard EN 61000-3-2 might be ammended (with A14) to redefine equipment classifications, specifically Class D. Does anyone have a reliable update on the situation? Will something be published in the Official Journal of the EC and at what point would this ammendment have the force of law? My apologies if I am hashing over a subject already discussed. Many thanks. Paul O'Shaughnessy Test Engineering Manager Affymetrix, Inc. Woburn, MA --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: Harmonic emissions
It was reported on here by someone that A14 was approved. The CENELC web site lists the proposed dop and dow. Since this is a basic standard, publication is necessary in the OJ for it to be effective. Richard Woods -- From: O'Shaughnessy, Paul [SMTP:paul_oshaughne...@geneticmicro.com] Sent: Tuesday, September 26, 2000 4:41 PM To: IEEE EMC Forum (E-mail) Subject: Harmonic emissions I am just rejoining the forum after a few weeks absence for vacation and server/domain changes. Early in September it appeared that the harmonic emissions standard EN 61000-3-2 might be ammended (with A14) to redefine equipment classifications, specifically Class D. Does anyone have a reliable update on the situation? Will something be published in the Official Journal of the EC and at what point would this ammendment have the force of law? My apologies if I am hashing over a subject already discussed. Many thanks. Paul O'Shaughnessy Test Engineering Manager Affymetrix, Inc. Woburn, MA --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: Harmonic emissions
Hello Group, Yes, A14 has been adopted, and in spite of the implementation date efforts are being made to make it valid per the first OJEC publication available , this means as soon as possible after 2001-1-1. I just received a notice (CLC/BT(SG)4087 with the UAP voting results, with a negative vote from Sweden only and the intention to make A14 available as fast as possible for ce-marking. Regards, Gert Gremmen, (Ing) ce-test, qualified testing === Web presence http://www.cetest.nl CE-shop http://www.cetest.nl/ce_shop.htm /-/ Compliance testing is our core business /-/ === -Original Message- From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf Of O'Shaughnessy, Paul Sent: Tuesday, September 26, 2000 10:41 PM To: IEEE EMC Forum (E-mail) Subject: Harmonic emissions I am just rejoining the forum after a few weeks absence for vacation and server/domain changes. Early in September it appeared that the harmonic emissions standard EN 61000-3-2 might be ammended (with A14) to redefine equipment classifications, specifically Class D. Does anyone have a reliable update on the situation? Will something be published in the Official Journal of the EC and at what point would this ammendment have the force of law? My apologies if I am hashing over a subject already discussed. Many thanks. Paul O'Shaughnessy Test Engineering Manager Affymetrix, Inc. Woburn, MA --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org attachment: Gert Gremmen.vcf
Stripline Cell Use for Radiated Emissions
All, We have been using a Comtest G310 0.7m x 0.7m x 0.7m Stripline cell for a few years now. For those unfamiliar with a stripline cell, it is a cubic chamber with a type-N coax connection on each side. The coax center conductor is routed through the bottom of the chamber under a false floor. The coax shield is connected to the outside of the chamber which is metal. The chamber is split in half with hinges and latches so that it opens/closes in clam shell fashion. The seam is gasketed and the entire outer shell of the chamber is metal so that it forms a faraday cage when closed. The inside of the chamber is lined with ferrite loaded foam to prevent reflections. I believe that there is a crude description of a stripline chamber in EN 61000-4-3 (IEC 1000-4-3). We purchased this system with a signal generator, an RF amplifier and software which allows us to perform radiated immunity testing in the chamber. The chamber is specified to be able to perform fully compliant radiated immunity testing on DUT's that fall within a 23cm x 23cm x23cm imaginary cube centered in the chamber. We have used the chamber for this purpose with good results. However, I have also used the chamber for radiated emissions measurements. This is where my question comes up. The chamber is not calibrated for emissions. However, over the last few years, every time I have taken a DUT to a 10meter OATS (at an outside test lab), I put the same DUT in the chamber and connect the chamber's coax line to our spectrum analyzer. I connect a 50 Ohm load to the coax connector on the other side of the chamber. I then take spectrum analyzer readings from the DUT. I repeat this process for all orientations of the DUT that I can set up. (i.e. face up, face down , on its side ...) I use a software program to collect and graph these readings. I have saved these spectrum analyzer readings as an unofficial archive in my files. I have used these archives as a baseline for many comparisons. I have used the archives to evaluate design changes on previously tested DUT's. (I have even included the graphs as updates to our Compliance Folders for DUT's that have been tested this way.) I have also used these archives to estimate how completely new DUT's would perform at a 10m OATS. To me it seems almost too easy. There are no ambient emissions in the chamber to cloud the measurements. I just get a little uptight when things seem too easy. I start wondering if I'm missing something. After having said the easy statement above, I should say that it is a little bit of a pain monitoring the DUT through the window, and sometimes I have trouble trying to loop the DUT's cabling into the compliant area of the chamber. I am also limited by size and cabling interfaces. I can only bring power and a couple of signal cables in through the filtered connectors in the chamber wall. Is there anybody in the group that would have an idea how accurate this type of testing is? I'm not looking for somebody to calculate the +/-dB uncertainty. I'm asking if there are basic physical properties (i.e. near field vs. far field, inaccurate measurement of cable emissions, fringing effects ...) that would make these types of comparisons risky?Is there anybody who has tried to correlate these types of measurements to an OATS? Are there ways to improve this test method (i.e. certain ways to route the DUT's cables) that would make this type of measurement more accurate. P.S. I do have an antenna to go with my spectrum analyzer, but our factory is in the middle of a city. And I'm cramped for room. I have tried some 1m prescan testing with my antenna with some success. The ambients are very hard to work through. Well there's some food for thought. Anybody care to bite? Chris Maxwell, Design Engineer GN Nettest Optical Division 6 Rhoads Drive, Building 4 Utica, NY 13502 PH: 315-797-4449 FAX: 315-797-8024 EMAIL: chr...@gnlp.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: Stripline Cell Use for Radiated Emissions
Hello Chris Maxwell, I have seen these things at several IEEE/Zurich EMC Symposia. I have listened to the sales people tell me how it works and how well it works, but I have to admit I have always been a skeptic. I have used various TEM devices in the past, mostly with good success. I have used the Military Standard stripline, the Crawford TEM cell, the GTEM, and a couple of other variations on the stripline, and I have used the OWL Chamber (open-wire line in a shielded room). I have experienced the limitations of these older methods, and I must say that the Crawford TEM and the GTEM have behaved the best. All that being said, I think you have an excellent opportunity to help the rest of us understand the advantages and limitations of the device you are using. I believe that you said you have much comparitive EM emission data in the device that you can compare to the OATS data you have. If I have not misread your note, and what I believe you said is true, you should be able to create a good comparison and, while you might not be able to pin down the real accuracy of the method, you could certainly pin down the difference between OATS and this Cell you have. At least as important, you could say if there was always some offset in one direction, i.e., higher or lower. It seems to me this would be a great service to yourself and to others; if you come out with bad looking comparisons, the vendor of your device may not like it. Regards, EdB -Original Message- From: Maxwell, Chris [mailto:chr...@gnlp.com] Sent: Wednesday, September 20, 2000 7:34 AM To: 'EMC-PSTC Internet Forum' Subject: Stripline Cell Use for Radiated Emissions All, We have been using a Comtest G310 0.7m x 0.7m x 0.7m Stripline cell for a few years now. For those unfamiliar with a stripline cell, it is a cubic chamber with a type-N coax connection on each side. The coax center conductor is routed through the bottom of the chamber under a false floor. The coax shield is connected to the outside of the chamber which is metal. The chamber is split in half with hinges and latches so that it opens/closes in clam shell fashion. The seam is gasketed and the entire outer shell of the chamber is metal so that it forms a faraday cage when closed. The inside of the chamber is lined with ferrite loaded foam to prevent reflections. I believe that there is a crude description of a stripline chamber in EN 61000-4-3 (IEC 1000-4-3). We purchased this system with a signal generator, an RF amplifier and software which allows us to perform radiated immunity testing in the chamber. The chamber is specified to be able to perform fully compliant radiated immunity testing on DUT's that fall within a 23cm x 23cm x23cm imaginary cube centered in the chamber. We have used the chamber for this purpose with good results. However, I have also used the chamber for radiated emissions measurements. This is where my question comes up. The chamber is not calibrated for emissions. However, over the last few years, every time I have taken a DUT to a 10meter OATS (at an outside test lab), I put the same DUT in the chamber and connect the chamber's coax line to our spectrum analyzer. I connect a 50 Ohm load to the coax connector on the other side of the chamber. I then take spectrum analyzer readings from the DUT. I repeat this process for all orientations of the DUT that I can set up. (i.e. face up, face down , on its side ...) I use a software program to collect and graph these readings. I have saved these spectrum analyzer readings as an unofficial archive in my files. I have used these archives as a baseline for many comparisons. I have used the archives to evaluate design changes on previously tested DUT's. (I have even included the graphs as updates to our Compliance Folders for DUT's that have been tested this way.) I have also used these archives to estimate how completely new DUT's would perform at a 10m OATS. To me it seems almost too easy. There are no ambient emissions in the chamber to cloud the measurements. I just get a little uptight when things seem too easy. I start wondering if I'm missing something. After having said the easy statement above, I should say that it is a little bit of a pain monitoring the DUT through the window, and sometimes I have trouble trying to loop the DUT's cabling into the compliant area of the chamber. I am also limited by size and cabling interfaces. I can only bring power and a couple of signal cables in through the filtered connectors in the chamber wall. Is there anybody in the group that would have an idea how accurate this type of testing is? I'm not looking for somebody to calculate the +/-dB uncertainty. I'm asking if there are basic physical properties (i.e. near field vs. far field, inaccurate measurement of cable emissions, fringing effects ...) that would make these types of comparisons risky?Is there anybody who has tried to correlate these types of measurements
AS/NZS 3548 - conducted emissions on telecom ports?
Hello group, Does Australia implement (or plan to implement) limits for conducted emissions on telecom ports as in EN 55022:1998? Also, who makes T-LISNs for these tests? Thanks, David. David Gelfand Regulatory Approvals Memotec Communications Inc. Montreal Canada --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Harmonics Emissions
Does anyone know if there is a power factor correction module available that can be fitted externally onto an existing power supply to enable it to pass the EN 61000-3-2 standard? We envision a module that would be installed between the AC mains source and the AC input to the power supply. The supply is a custom-designed switched mode supply and the product it goes into is such a low volume that we don't want to redesign the power supply front end to add PFC unless we absolutely have to. The supply operates at 230V/50Hz single phase and is rated for 600W. Jim Hulbert Senior Engineer Pitney Bowes --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re:RE: Harmonics Emissions
forwarding for johnwag...@avaya.com Reply Separator Subject:RE: Harmonics Emissions Author: Wagner; John P (John) johnwag...@avaya.com List-Post: emc-pstc@listserv.ieee.org Date: 9/12/00 3:01 PM A ferroresonant transformer such as those made (formerly at least) by Sola will do the job. So will a UPS with a power factor corrected front end. John P. Wagner Lucent Technologies, Bell Labs 11900 N. Pecos St, Room 2F58 Denver CO 80234 email: johnwag...@lucent.com phone: 303 538-4241 fax: 303 538-5211 -- From: Jim Hulbert[SMTP:hulbe...@pb.com] Reply To: Jim Hulbert Sent: Tuesday, September 12, 2000 11:12 AM To: emc-p...@ieee.org Subject: Harmonics Emissions Does anyone know if there is a power factor correction module available that can be fitted externally onto an existing power supply to enable it to pass the EN 61000-3-2 standard? We envision a module that would be installed between the AC mains source and the AC input to the power supply. The supply is a custom-designed switched mode supply and the product it goes into is such a low volume that we don't want to redesign the power supply front end to add PFC unless we absolutely have to. The supply operates at 230V/50Hz single phase and is rated for 600W. Jim Hulbert Senior Engineer Pitney Bowes --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org Received: from ruebert.ieee.org ([199.172.136.3]) by mail.monarch.com with SMTP (IMA Internet Exchange 3.14) id 56C8; Tue, 12 Sep 2000 17:03:38 -0700 Received: by ruebert.ieee.org (8.9.3/8.9.3)id RAA28982 Received: from gemini3.ieee.org by ruebert.ieee.org (8.9.3/8.9.3) with ESMTP id RAA27968; Tue, 12 Sep 2000 17:01:40 -0400 (EDT) Received: from hoemail2.firewall.lucent.com (hoemail2.lucent.com [192.11.226.163]) by gemini3.ieee.org (8.9.3/8.9.3) with ESMTP id RAA25800 for emc-p...@ieee.org; Tue, 12 Sep 2000 17:01:38 -0400 (EDT) Received: from hoemail2.firewall.lucent.com (localhost [127.0.0.1]) by hoemail2.firewall.lucent.com (Pro-8.9.3/8.9.3) with ESMTP id RAA13015 for emc-p...@ieee.org; Tue, 12 Sep 2000 17:01:38 -0400 (EDT) Received: from co7010exch002h.wins.lucent.com (h135-39-163-77.lucent.com [135.39.163.77]) by hoemail2.firewall.lucent.com (Pro-8.9.3/8.9.3) with ESMTP id RAA13008 for emc-p...@ieee.org; Tue, 12 Sep 2000 17:01:38 -0400 (EDT) Received: by CO7010EXCH002H with Internet Mail Service (5.5.2650.21) id R7NJPBAG; Tue, 12 Sep 2000 15:01:38 -0600 Message-ID: e4222c3b82dcd111a3d900a0c9a92f4c030ef...@cof110exch001u.dr.lucent.com From: Wagner, John P (John) johnwag...@avaya.com To: emc-p...@ieee.org, 'Jim Hulbert' hulbe...@pb.com Subject: RE: Harmonics Emissions List-Post: emc-pstc@listserv.ieee.org Date: Tue, 12 Sep 2000 15:01:37 -0600 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2650.21) Content-Type: text/plain X-Resent-To: emc-pstc-ad...@ieee.org Precedence: bulk --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: R: R: Conducted Emissions on Telecom Ports
The defined I/O coupling methods for EN55022:1997 do not appear to accurately depict real-world shielding provided by twisted pair wiring, almost as if the test method were rigged against passing EMI with T-P cable. Considerable study went into development of twisted pair connectivity rules for each ANSI/IEEE 802.x LAN technology, emissions, immunity, cable grade etc., including coupling (remember TokenRing was 4 and 16 MHz, and Ethernet was 10 MHz so the harmonics were there). David __ Reply Separator _ Subject: Re: R: R: Conducted Emissions on Telecom Ports Author: Ken Javor SMTP:ken.ja...@emccompliance.com at ADEMCONET List-Post: emc-pstc@listserv.ieee.org Date:9/8/2000 5:31 PM The point is that RE/CE protect broadcast bands. Making an RE measurement (E or H field, regardless) from a LAN line a couple meters long is not representative of what you would measure if the LAN line were significantly longer, as it might be in situ. Therefore a CE measurement can be better correlated to predicted RE from a much longer line (at frequencies where the tested LAN line is electrically short. -- From: Paolo Roncone paolo.ronc...@compuprint.it To: 'Ken Javor' ken.ja...@emccompliance.com, 'Cortland Richmond' 72146@compuserve.com Cc: 'emc-p...@ieee.org' emc-p...@ieee.org Subject: R: R: Conducted Emissions on Telecom Ports Date: Fri, Sep 8, 2000, 3:51 AM Ken and Cortland and many others that entered this subject : First, radiated emissions are best measured with radiated (not conducted) measurements. There is a correlation between CM currents and RE but that's not all (resonances, cable layout etc. count a lot). Second, you say that CE are easier to measure than RE ? Agree if you talk about emissions on AC power cords (as per CISPR22 and FCC part 15). But for the new requirements on telecom ports, I suggest you to take a look at the new (3.ed.) CISPR22 or EN55022 (sec. 9.5 + annex C.1) and may be you change your opinion ! Radiated emissions above 30 MHz are already covered. If you wanna take care of lower frequencies ( 30 MHz) take a loop antenna (remember the old VDE rules ?) and measure radiated H-fields with your system in the same (typical) layout used for the higher frequencies (with whatever cables you specify, UTS, STP etc.). I am sure that is much quicker, easier and repeatable than all the nonsense (ISNs, CDNs, clamps, current probes, capacitive probes, ferrites, 150 ohm resistors, signal generators, impedance measurements, voltage measurements, current measurements and more) in the new CISPR22. As for the question of outside world, I think in this ever more connected world the border line between INSIDE and OUTSIDE is getting more and more blurred, BUT I also think that a line must be drawn by the standard bodies, otherwise it's gonna really get too much confusing (hope some CISPR/CENELEC member gets it). If we spill over the line (office, floor, building... whatever), emissions requirements are triggered. But within that line it's to be considered an intra-system (what's the system ? that's another good question to be settled) interference potential and the manufacturer should take care of it without need of enforcement because he has all the interest in making a product (system) that works properly and reliably. One last point: based on David Sterner's note, looks to me that North America has a pretty extensive Ethernet and-the-like network. I honestly don't know if the FCC has already enforced emission limits on LAN ports. Anyway, based on David's note looks like there are no complaits of interference with TV and telephones. And please note, this is the very bottom line of it. Emission limits should be intended to protect public services ... and physics works the same on both sides of the Atlantic... or not My personal opinion ... Paolo -Messaggio originale- Da: Ken Javor [SMTP:ken.ja...@emccompliance.com] Inviato: giovedì 7 settembre 2000 18.43 A: Paolo Roncone; 'eric.lif...@ni.com' Cc: 'emc-p...@ieee.org' Oggetto: Re: R: Conducted Emissions on Telecom Ports Although I don't work commercial EMC on a regular basis and I do not know over what frequency range the telecom port CE are controlled (I assume here 150 kHz - 30 MHz), I believe that there is a mistaken premise inherent in the comments to which I am responding. The purpose of controlling common mode CE on any port is not to protect equipment at the other end of the cable, or other co-sited cables, but rather to control radiated emissions in a frequency range in which CE are easier to measure than RE. In turn, the purpose of controlling RE is to protect broadcast radio reception. -- From: Paolo Roncone paolo.ronc...@compuprint.it To: 'eric.lif...@ni.com' eric.lif
Re: R: Conducted Emissions on Telecom Ports
Steve: Please tell me more about the immunity standards- they are non existent in Canada Ralph Cameron EMC Consulting and Suppression of Consumer Electronic Equipment (After sale) p.s Ever listen to the radio near some home treadmills? - Original Message - From: Steve Grobe ste...@transition.com To: ieee pstc list emc-p...@ieee.org Sent: Thursday, September 07, 2000 1:35 PM Subject: RE: R: Conducted Emissions on Telecom Ports Has anyone seen problems with ethernet and conducted emissions? I have a home office with 4 PCs networked with ethernet running over UTP and I haven't seen much of a problem. Granted, the longest cable run I have is to a file server in the basement (about 10 meters) but both my AM radio and my shortwave set seem to work just fine. The only thing I remember picking up is 20MHz on the shortwave set. (Most 10Mbit ethernet devices use a 20MHz clock.) At work we have both 10 and 100Mbit ethernet (150-200 nodes) and the AM reception is really bad but I attribute that to the building (big steel and brick box) more than noise as reception improves as you get closer to a window. I haven't tried the shortwave at work being that shortwave reception is usually bad during the day anyway. As far as telephone lines are concerned my ears don't pick up much noise above 19kHz. I would think anything else would be covered by immunity standards. Steve -Original Message- From: Cortland Richmond [mailto:72146@compuserve.com] Sent: Thursday, September 07, 2000 11:01 AM To: Paolo Roncone; ieee pstc list Subject: Re: R: Conducted Emissions on Telecom Ports Paolo Roncone wrote: The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. I disagree. The purpose of emissions standards is to prevent interference. Some are to similar functions, some are to other media. There is no interface for interference at which point the manufacturer may say: Interference when you use this isn't our problem. We may say: Use shielded cable, or Put a ferrite on your cable, but we can't evade the physical fact that it is our own equipment which is the source of interference, and the cable is its antenna. It does not matter that we do not own the cable; if you plug it in and there is interference, it is up to the people who made the equipment to see the interference reduced. There is no transfer of ownership for radio waves. Granted, to call a LAN cable telecommunications is a clumsy construction of the regulation. But those who grasp at that straw to save a few currency units will find themselves later regretting that they have done so. If you are beaten and robbed for a display of wealth, it is no use protesting that the money was counterfeit. Cortland Richmond (I speak for myself alone and not for my employer) == Original Message Follows Date: 07-Sep-00 07:48:16 MsgID: 1072-46656 ToID: 72146,373 From: Paolo Roncone INTERNET:paolo.ronc...@compuprint.it Subj: R: Conducted Emissions on Telecom Ports Chrg: $0.00 Imp: Norm Sens: StdReceipt: NoParts: 1 From: Paolo Roncone paolo.ronc...@compuprint.it Subject: R: Conducted Emissions on Telecom Ports Date: Thu, 7 Sep 2000 16:45:03 +0200 Reply-To: Paolo Roncone paolo.ronc...@compuprint.it Hi Eric, I 100% agree with you. The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. The problem is (as pointed out in one of the previous notes) that the new CISPR22 / EN55022 standard clearly includes LAN ports in the definition of telecommunications ports (section 3.6) no matter if they connect to the outside world or not. Regards, Paolo Roncone Compuprint s.p.a. Italy -Messaggio originale- Da: eric.lif...@ni.com [SMTP:eric.lif...@ni.com] Inviato:mercoledì 6 settembre 2000 17.55 A: emc-p...@ieee.org Oggetto:Re: Conducted Emissions on Telecom Ports All, As a not-quite-outside-observer (strictly EN 55011 here) of this thread, it's not fun seeing LAN ports classified as telecom; IMO that's overkill for the folks using EN 55022. Up till now, I considered a port to be telecom only if it connects a client facility to a carrier's network (DSL, ISDN, T1 and so on). With repeaters every 5 meters, USB and 1394 can support a bus long enough to connect between adjacent buildings. So, I wonder if some fanatic will soon be promoting USB/1394 ports as telecom? If Chris is right, and the EN 55022 version of the old telecom port conducted emission standard was intended to protect other telecom signals in a bundle, then I would think that this test is clearly redundant to the immunity
RE: Conducted Emissions on Telecom Ports
You've got it just about 100% correct. The DoW for EN 55022:1998 is 1 August 2001. It is effective right now if you want to use it. It is the only game in town as of the DoW. Ghery Pettit -Original Message- From: Pryor McGinnis [mailto:c...@prodigy.net] Sent: Tuesday, September 05, 2000 8:37 AM To: Gary McInturff; Pettit, Ghery; david_ster...@ademco.com; emc-p...@ieee.org Subject: Re: Conducted Emissions on Telecom Ports Reference CISPR 22:1997, Clause 3.5 telecommunication ports Ports which are intended to be connected to telecommunication networks (e.g. public switched telecommunication networks, integrated services digital networks), local area networks (e.g. Ethernet, Token Ring) and similar networks. This definition indicates that LAN boards such as Ethernet Token Ring will be treated as telecommunication ports and will require conducted emissions to be performed as part of the emission testing. This definition is carried over to EN 55022 and is effective next year. Am I misinterpreting something here? Thanks Pryor - Original Message - From: Gary McInturff gary.mcintu...@worldwidepackets.com To: 'Pryor McGinnis' c...@prodigy.net; Pettit, Ghery ghery.pet...@intel.com; david_ster...@ademco.com; emc-p...@ieee.org Sent: Tuesday, September 05, 2000 10:54 AM Subject: RE: Conducted Emissions on Telecom Ports Define telecom port. A LAN port isn't neccessarily a LAN port. Ethernet ports do not connect directly to the Telecommunications network - a necessary condition before being a telecommunications port. LANS and MANS operate all of the time without any use of any telecommunications equipment. Generally, Ethernet or Fast Ethernet for short distances and Gig Ethernet for longer distances. IF -- the telecommunications lines are needed there is some sort of bridge that takes the ethernet and its digitized Voice over Internet Protocol (Voip) and does all of the phone stuff and makes the actual metallic connection. That birdge has the only telecommunication ports on it. Gary -Original Message- From: Pryor McGinnis [mailto:c...@prodigy.net] Sent: Thursday, August 31, 2000 6:24 AM To: Pettit, Ghery; david_ster...@ademco.com; emc-p...@ieee.org Subject: Re: Conducted Emissions on Telecom Ports Confusing isn't? - Original Message - From: Pettit, Ghery ghery.pet...@intel.com To: david_ster...@ademco.com; emc-p...@ieee.org; c...@prodigy.net Sent: Wednesday, August 30, 2000 5:40 PM Subject: RE: Conducted Emissions on Telecom Ports Actually, it's August 1, 2001 as posted in the OJ on January 25th of this year. You've got 1 less month to start testing to the new standard. Ghery Pettit Intel -Original Message- From: david_ster...@ademco.com [mailto:david_ster...@ademco.com] Sent: Wednesday, August 30, 2000 2:04 PM To: emc-p...@ieee.org; c...@prodigy.net Subject: RE: Conducted Emissions on Telecom Ports The date of withdrawal of EN 55022:1998 is September 1, 2001. Look at the NIC manual's DofC --- the mfgr. may not be declaring compliance to conducted emissions yet. __ Reply Separator _ Subject: Re: Conducted Emissions on Telecom Ports Author: Pryor McGinnis SMTP:c...@prodigy.net at ADEMCONET Date:8/30/2000 10:31 AM Hello All, The question originated from a manufacturer of LAN boards who sells to end users and to manufacturer's who integrate the LAN boards into end products. I advised the LAN board manufacturer that conducted emissions would be required (with boards installed in typical host) on all LAN boards sold to end users and manufacturers of products that integrated LAN boards should test the ports for conducted emission in their end product. The LAN board manufacturer questioned double testing of the LAN boards. His concern is that boards that pass CE in a typical host may not pass in another manufacturer's end product (rub of the green). The LAN Board manufacturer ask for second opinions. Many thanks for your answers. Best Regards, Pryor -Original Message- From: Pryor McGinnis [SMTP:c...@prodigy.net] Sent: Tuesday, August 29, 2000 12:35 PM To: emc-pstc Subject: Conducted Emissions on Telecom Ports Below is a message from a non emc-pstc member. If a manufacturer purchases LAN boards which have been tested for conducted emissions in a host, is the manufacturer required to retest the LAN Ports for conducted emissions if the manufacturer sells his product with the LAN board installed? I am very interested in your comments. Best Regards, Pryor McGinnis c...@prodigy.net mailto:c...@prodigy.net www.ctl-lab.com http://www.ctl-lab.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion
Re: R: R: Conducted Emissions on Telecom Ports
The point is that RE/CE protect broadcast bands. Making an RE measurement (E or H field, regardless) from a LAN line a couple meters long is not representative of what you would measure if the LAN line were significantly longer, as it might be in situ. Therefore a CE measurement can be better correlated to predicted RE from a much longer line (at frequencies where the tested LAN line is electrically short. -- From: Paolo Roncone paolo.ronc...@compuprint.it To: 'Ken Javor' ken.ja...@emccompliance.com, 'Cortland Richmond' 72146@compuserve.com Cc: 'emc-p...@ieee.org' emc-p...@ieee.org Subject: R: R: Conducted Emissions on Telecom Ports Date: Fri, Sep 8, 2000, 3:51 AM Ken and Cortland and many others that entered this subject : First, radiated emissions are best measured with radiated (not conducted) measurements. There is a correlation between CM currents and RE but that's not all (resonances, cable layout etc. count a lot). Second, you say that CE are easier to measure than RE ? Agree if you talk about emissions on AC power cords (as per CISPR22 and FCC part 15). But for the new requirements on telecom ports, I suggest you to take a look at the new (3.ed.) CISPR22 or EN55022 (sec. 9.5 + annex C.1) and may be you change your opinion ! Radiated emissions above 30 MHz are already covered. If you wanna take care of lower frequencies ( 30 MHz) take a loop antenna (remember the old VDE rules ?) and measure radiated H-fields with your system in the same (typical) layout used for the higher frequencies (with whatever cables you specify, UTS, STP etc.). I am sure that is much quicker, easier and repeatable than all the nonsense (ISNs, CDNs, clamps, current probes, capacitive probes, ferrites, 150 ohm resistors, signal generators, impedance measurements, voltage measurements, current measurements and more) in the new CISPR22. As for the question of outside world, I think in this ever more connected world the border line between INSIDE and OUTSIDE is getting more and more blurred, BUT I also think that a line must be drawn by the standard bodies, otherwise it's gonna really get too much confusing (hope some CISPR/CENELEC member gets it). If we spill over the line (office, floor, building... whatever), emissions requirements are triggered. But within that line it's to be considered an intra-system (what's the system ? that's another good question to be settled) interference potential and the manufacturer should take care of it without need of enforcement because he has all the interest in making a product (system) that works properly and reliably. One last point: based on David Sterner's note, looks to me that North America has a pretty extensive Ethernet and-the-like network. I honestly don't know if the FCC has already enforced emission limits on LAN ports. Anyway, based on David's note looks like there are no complaits of interference with TV and telephones. And please note, this is the very bottom line of it. Emission limits should be intended to protect public services ... and physics works the same on both sides of the Atlantic... or not My personal opinion ... Paolo -Messaggio originale- Da: Ken Javor [SMTP:ken.ja...@emccompliance.com] Inviato: giovedì 7 settembre 2000 18.43 A: Paolo Roncone; 'eric.lif...@ni.com' Cc: 'emc-p...@ieee.org' Oggetto: Re: R: Conducted Emissions on Telecom Ports Although I don't work commercial EMC on a regular basis and I do not know over what frequency range the telecom port CE are controlled (I assume here 150 kHz - 30 MHz), I believe that there is a mistaken premise inherent in the comments to which I am responding. The purpose of controlling common mode CE on any port is not to protect equipment at the other end of the cable, or other co-sited cables, but rather to control radiated emissions in a frequency range in which CE are easier to measure than RE. In turn, the purpose of controlling RE is to protect broadcast radio reception. -- From: Paolo Roncone paolo.ronc...@compuprint.it To: 'eric.lif...@ni.com' eric.lif...@ni.com Cc: 'emc-p...@ieee.org' emc-p...@ieee.org Subject: R: Conducted Emissions on Telecom Ports Date: Thu, Sep 7, 2000, 9:45 AM Hi Eric, I 100% agree with you. The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. The problem is (as pointed out in one of the previous notes) that the new CISPR22 / EN55022 standard clearly includes LAN ports in the definition of telecommunications ports (section 3.6) no matter if they connect to the outside world or not. Regards, Paolo Roncone Compuprint s.p.a. Italy --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail
RE: R: Conducted Emissions on Telecom Ports
Paolo, Physics does work the same on both side of the Atlantic, but human rationale does not necessarily! Tania Grant, tgr...@lucent.com Lucent Technologies, Switching Solutions Group Intelligent Network and Messaging Solutions -- From: Paolo Roncone[SMTP:paolo.ronc...@compuprint.it] Reply To: Paolo Roncone Sent: Friday, September 08, 2000 3:51 AM To: 'Ken Javor'; 'Cortland Richmond' Cc: 'emc-p...@ieee.org' Subject: R: R: Conducted Emissions on Telecom Ports Ken and Cortland and many others that entered this subject : First, radiated emissions are best measured with radiated (not conducted) measurements. There is a correlation between CM currents and RE but that's not all (resonances, cable layout etc. count a lot). Second, you say that CE are easier to measure than RE ? Agree if you talk about emissions on AC power cords (as per CISPR22 and FCC part 15). But for the new requirements on telecom ports, I suggest you to take a look at the new (3.ed.) CISPR22 or EN55022 (sec. 9.5 + annex C.1) and may be you change your opinion ! Radiated emissions above 30 MHz are already covered. If you wanna take care of lower frequencies ( 30 MHz) take a loop antenna (remember the old VDE rules ?) and measure radiated H-fields with your system in the same (typical) layout used for the higher frequencies (with whatever cables you specify, UTS, STP etc.). I am sure that is much quicker, easier and repeatable than all the nonsense (ISNs, CDNs, clamps, current probes, capacitive probes, ferrites, 150 ohm resistors, signal generators, impedance measurements, voltage measurements, current measurements and more) in the new CISPR22. As for the question of outside world, I think in this ever more connected world the border line between INSIDE and OUTSIDE is getting more and more blurred, BUT I also think that a line must be drawn by the standard bodies, otherwise it's gonna really get too much confusing (hope some CISPR/CENELEC member gets it). If we spill over the line (office, floor, building... whatever), emissions requirements are triggered. But within that line it's to be considered an intra-system (what's the system ? that's another good question to be settled) interference potential and the manufacturer should take care of it without need of enforcement because he has all the interest in making a product (system) that works properly and reliably. One last point: based on David Sterner's note, looks to me that North America has a pretty extensive Ethernet and-the-like network. I honestly don't know if the FCC has already enforced emission limits on LAN ports. Anyway, based on David's note looks like there are no complaits of interference with TV and telephones. And please note, this is the very bottom line of it. Emission limits should be intended to protect public services ... and physics works the same on both sides of the Atlantic... or not My personal opinion ... Paolo -Messaggio originale- Da: Ken Javor [SMTP:ken.ja...@emccompliance.com] Inviato: giovedì 7 settembre 2000 18.43 A:Paolo Roncone; 'eric.lif...@ni.com' Cc: 'emc-p...@ieee.org' Oggetto: Re: R: Conducted Emissions on Telecom Ports Although I don't work commercial EMC on a regular basis and I do not know over what frequency range the telecom port CE are controlled (I assume here 150 kHz - 30 MHz), I believe that there is a mistaken premise inherent in the comments to which I am responding. The purpose of controlling common mode CE on any port is not to protect equipment at the other end of the cable, or other co-sited cables, but rather to control radiated emissions in a frequency range in which CE are easier to measure than RE. In turn, the purpose of controlling RE is to protect broadcast radio reception. -- From: Paolo Roncone paolo.ronc...@compuprint.it To: 'eric.lif...@ni.com' eric.lif...@ni.com Cc: 'emc-p...@ieee.org' emc-p...@ieee.org Subject: R: Conducted Emissions on Telecom Ports Date: Thu, Sep 7, 2000, 9:45 AM Hi Eric, I 100% agree with you. The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. The problem is (as pointed out in one of the previous notes) that the new CISPR22 / EN55022 standard clearly includes LAN ports in the definition of telecommunications ports (section 3.6) no matter if they connect to the outside world or not. Regards, Paolo Roncone Compuprint s.p.a. Italy --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list
RE: R: R: Conducted Emissions on Telecom Ports
All, As Ghery reported before (lost in the recent threads, but copied below), the closely related issue cf definition creepage is being addressed by CISPR SC G and is already is CDV stage but not yet FDIS. If it isn't already too late, this might be the best or only opportunity we'll get for bring the issue up for discussion in a CISPR committee within the next couple of years. This would be the opportunity to bring together in some way (?) the designers of Ethernet and the CISPR committee, so whatever the outcome we can agree the issue was examined with due engineering dilligence. Regards, Eric Lifsey Please respond to Pettit, Ghery ghery.pet...@intel.com To: Eric Lifsey/AUS/NIC@NIC, emc-p...@ieee.org cc: Subject: RE: Conducted Emissions on Telecom Ports This sort of question has already come up in CISPR SC G (the owner of CISPR 22). There is a CDV (Committee Draft for Vote) being prepared that, if adopted as a Final Draft International Standard (FDIS), will put a halt to the definition creep that has been happening with this issue. The text doesn't get rid of LANs as a telecom port, but it does prevent administrations from calling things like RS-232 (yes, Australia has tried to justify this as a telecom port), USB, 1393, etc telecom ports. Nothing happens fast in the IEC, so don't hold your breath waiting for this change to happen, but we are working on it. When the CDV comes out there will be a voting period on it and if it passes, it will then be re-issued as an FDIS for final vote. I wouldn't expect any final action for at least a year or more. Ghery Pettit Intel Member, US CISPR G TAG --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: R: R: Conducted Emissions on Telecom Ports
Paolo, You bring up an interesting point about FCC. FCC recognizes CISPR 22:1985 is as an alternative test method. The 1985 version does not specify emissions on LAN or telco. FCC Part 68 specifies conducted emissions only on mains cables over 450kHz to 30MHz with slightly different limits. There seems to be considerable interest in requesting a review of the need for conducted emissions requirements for LANS, not to mention installation cost (STP cost differential, clumsy routing, earthing considerations). What is our next step to get a formal review? David __ Reply Separator _ Subject: R: R: Conducted Emissions on Telecom Ports Author: Paolo Roncone SMTP:paolo.ronc...@compuprint.it at ADEMCONET List-Post: emc-pstc@listserv.ieee.org Date:9/8/2000 6:51 AM Ken and Cortland and many others that entered this subject : First, radiated emissions are best measured with radiated (not conducted) measurements. There is a correlation between CM currents and RE but that's not all (resonances, cable layout etc. count a lot). Second, you say that CE are easier to measure than RE ? Agree if you talk about emissions on AC power cords (as per CISPR22 and FCC part 15). But for the new requirements on telecom ports, I suggest you to take a look at the new (3.ed.) CISPR22 or EN55022 (sec. 9.5 + annex C.1) and may be you change your opinion ! Radiated emissions above 30 MHz are already covered. If you wanna take care of lower frequencies ( 30 MHz) take a loop antenna (remember the old VDE rules ?) and measure radiated H-fields with your system in the same (typical) layout used for the higher frequencies (with whatever cables you specify, UTS, STP etc.). I am sure that is much quicker, easier and repeatable than all the nonsense (ISNs, CDNs, clamps, current probes, capacitive probes, ferrites, 150 ohm resistors, signal generators, impedance measurements, voltage measurements, current measurements and more) in the new CISPR22. As for the question of outside world, I think in this ever more connected world the border line between INSIDE and OUTSIDE is getting more and more blurred, BUT I also think that a line must be drawn by the standard bodies, otherwise it's gonna really get too much confusing (hope some CISPR/CENELEC member gets it). If we spill over the line (office, floor, building... whatever), emissions requirements are triggered. But within that line it's to be considered an intra-system (what's the system ? that's another good question to be settled) interference potential and the manufacturer should take care of it without need of enforcement because he has all the interest in making a product (system) that works properly and reliably. One last point: based on David Sterner's note, looks to me that North America has a pretty extensive Ethernet and-the-like network. I honestly don't know if the FCC has already enforced emission limits on LAN ports. Anyway, based on David's note looks like there are no complaits of interference with TV and telephones. And please note, this is the very bottom line of it. Emission limits should be intended to protect public services ... and physics works the same on both sides of the Atlantic... or not My personal opinion ... Paolo -Messaggio originale- Da: Ken Javor [SMTP:ken.ja...@emccompliance.com] Inviato: giovedì 7 settembre 2000 18.43 A: Paolo Roncone; 'eric.lif...@ni.com' Cc: 'emc-p...@ieee.org' Oggetto: Re: R: Conducted Emissions on Telecom Ports Although I don't work commercial EMC on a regular basis and I do not know over what frequency range the telecom port CE are controlled (I assume here 150 kHz - 30 MHz), I believe that there is a mistaken premise inherent in the comments to which I am responding. The purpose of controlling common mode CE on any port is not to protect equipment at the other end of the cable, or other co-sited cables, but rather to control radiated emissions in a frequency range in which CE are easier to measure than RE. In turn, the purpose of controlling RE is to protect broadcast radio reception. -- From: Paolo Roncone paolo.ronc...@compuprint.it To: 'eric.lif...@ni.com' eric.lif...@ni.com Cc: 'emc-p...@ieee.org' emc-p...@ieee.org Subject: R: Conducted Emissions on Telecom Ports Date: Thu, Sep 7, 2000, 9:45 AM Hi Eric, I 100% agree with you. The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. The problem is (as pointed out in one of the previous notes) that the new CISPR22 / EN55022 standard clearly includes LAN ports in the definition of telecommunications ports (section 3.6) no matter
Re: R: Conducted Emissions on Telecom Ports
Ken, that is not what Mike is saying. Mike's statment was to the effect that if the noise can get out of the EUT then noise from another source can get in. A point of exit can also be a point of entry for EMI. This applies to all types of launching mechanisms, not just cables. Also, just because a piece of equipemnt is passing CE or any emissions does not guarrenty that it will not cause a problem with other equipment. Coupling between adjacent cabling can cause EMC issues even if both unit pass CE. Primarily, all emissions limits, CE and RE, exist to provide a level of protection for communitcations over the air. Equipment protection is secondary. Keeping equipment clean at the source goes a long way to protect it from outside influences. Guy Story, KC5GOI Compliance Technician Interphase Corporation Dallas Texas phone: 214.654.5161 fax: 214.654.5406 - Original Message - From: Ken Javor ken.ja...@emccompliance.com To: michael.sundst...@nokia.com; paolo.ronc...@compuprint.it; eric.lif...@ni.com Cc: emc-p...@ieee.org Sent: Thursday, September 07, 2000 10:17 PM Subject: Re: R: Conducted Emissions on Telecom Ports So you are saying that an emission limit was imposed to improve immunity of the self-same equipment? I have to go on record disagreeing with that interpretation. As for protection of nearby circuits, my guess is that if you calculate coupling from a cable just meeting your telecom port CE limit to an adjacent cable, you will find that even common mode coupling is orders of magnitude below the intentional signal carried in the adjacent victim cable. I say this in full ignorance of just what that CE limit is, since I know that a CE limit designed to protect against rfi will more than protect against cable-to-cable coupling. -- From: michael.sundst...@nokia.com To: ken.ja...@emccompliance.com, paolo.ronc...@compuprint.it, eric.lif...@ni.com Cc: emc-p...@ieee.org Subject: RE: R: Conducted Emissions on Telecom Ports Date: Thu, Sep 7, 2000, 5:01 PM Actually it's to reduce interference to one's own equipment, (if it emits it - it's also susceptible to it). It also has the effect of reducing interference to other near by equipment. Michael Sundstrom Nokia Mobile Phones, PCC EMC Technician cube 4E : 390B phone: 972-374-1462 mobile: 817-917-5021 michael.sundst...@nokia.com amateur call: KB5UKT --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
R: R: Conducted Emissions on Telecom Ports
Ken and Cortland and many others that entered this subject : First, radiated emissions are best measured with radiated (not conducted) measurements. There is a correlation between CM currents and RE but that's not all (resonances, cable layout etc. count a lot). Second, you say that CE are easier to measure than RE ? Agree if you talk about emissions on AC power cords (as per CISPR22 and FCC part 15). But for the new requirements on telecom ports, I suggest you to take a look at the new (3.ed.) CISPR22 or EN55022 (sec. 9.5 + annex C.1) and may be you change your opinion ! Radiated emissions above 30 MHz are already covered. If you wanna take care of lower frequencies ( 30 MHz) take a loop antenna (remember the old VDE rules ?) and measure radiated H-fields with your system in the same (typical) layout used for the higher frequencies (with whatever cables you specify, UTS, STP etc.). I am sure that is much quicker, easier and repeatable than all the nonsense (ISNs, CDNs, clamps, current probes, capacitive probes, ferrites, 150 ohm resistors, signal generators, impedance measurements, voltage measurements, current measurements and more) in the new CISPR22. As for the question of outside world, I think in this ever more connected world the border line between INSIDE and OUTSIDE is getting more and more blurred, BUT I also think that a line must be drawn by the standard bodies, otherwise it's gonna really get too much confusing (hope some CISPR/CENELEC member gets it). If we spill over the line (office, floor, building... whatever), emissions requirements are triggered. But within that line it's to be considered an intra-system (what's the system ? that's another good question to be settled) interference potential and the manufacturer should take care of it without need of enforcement because he has all the interest in making a product (system) that works properly and reliably. One last point: based on David Sterner's note, looks to me that North America has a pretty extensive Ethernet and-the-like network. I honestly don't know if the FCC has already enforced emission limits on LAN ports. Anyway, based on David's note looks like there are no complaits of interference with TV and telephones. And please note, this is the very bottom line of it. Emission limits should be intended to protect public services ... and physics works the same on both sides of the Atlantic... or not My personal opinion ... Paolo -Messaggio originale- Da: Ken Javor [SMTP:ken.ja...@emccompliance.com] Inviato:giovedì 7 settembre 2000 18.43 A: Paolo Roncone; 'eric.lif...@ni.com' Cc: 'emc-p...@ieee.org' Oggetto:Re: R: Conducted Emissions on Telecom Ports Although I don't work commercial EMC on a regular basis and I do not know over what frequency range the telecom port CE are controlled (I assume here 150 kHz - 30 MHz), I believe that there is a mistaken premise inherent in the comments to which I am responding. The purpose of controlling common mode CE on any port is not to protect equipment at the other end of the cable, or other co-sited cables, but rather to control radiated emissions in a frequency range in which CE are easier to measure than RE. In turn, the purpose of controlling RE is to protect broadcast radio reception. -- From: Paolo Roncone paolo.ronc...@compuprint.it To: 'eric.lif...@ni.com' eric.lif...@ni.com Cc: 'emc-p...@ieee.org' emc-p...@ieee.org Subject: R: Conducted Emissions on Telecom Ports Date: Thu, Sep 7, 2000, 9:45 AM Hi Eric, I 100% agree with you. The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. The problem is (as pointed out in one of the previous notes) that the new CISPR22 / EN55022 standard clearly includes LAN ports in the definition of telecommunications ports (section 3.6) no matter if they connect to the outside world or not. Regards, Paolo Roncone Compuprint s.p.a. Italy --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Conducted Emissions on Telecom Ports
Hi All, I could not resist adding my two cents worth. In the last several years I spent at Bell Labs in NJ (moved to CA 4 1/2 years ago), part of my funding came from a group that was responsible for UTP (Cat 5) and associated hardware. On immunity performance, we were not able to find a shielded system that would outperform UTP using the interface circuits I had design input on. (When I first proposed the circuitry, the group had an internal Bell Labs balun expert review it. He did not understand how it worked.) Emissions were lower compared to several shielded systems we measured. The data was published at EMC Roma about 1995. If I can dig it up, I will try to post it to my site later this month. Several formats of data were used including 100 Mb speeds. We even did a demonstration of a 600 Mb over UTP cable (section of the cable is within sight at this moment). The conducted emissions on telecom leads spec was just being written at that time. As I recall, we were pretty close to meeting it except the method in the proposed standard was not workable, so we used current probes and moving the cables to maximize current (just like RE testing). The net result is that UTP with the appropriate interface circuits (not expensive, either) performs quite well compared to STP systems. If anyone wants more into, email directly to me and I will try and hook them up with someone at Bell Labs in NJ who is currently on the project. It's been a while and I am not sure what the present status of that work is. BTW, I recall that starting with a VERY well balanced source/load, Cat5 cable inherently had about 12 dB better balance, and therefore performance, than Cat3 for the high frequency immunity/radiated measurements that I made. I did not get much into the signal transmission differences between Cat3 and Cat5 though. Doug Gary McInturff wrote: Another little nagging problem exists. Without going into the whole historically precedence UTP was a pretty important reason why ethernet was adopted so widely. The wiring was pretty much in place because of the cables that had been run for connecting office telephones etc. People don't want to drag in new cables (STP) because of the cost. I happen to agree with you assements below and wouldn't even consider UTP if it weren't for the existing installs and the 805 standard that (prefers?) it. Thanks Gary -Original Message- -- --- ___ _ Doug Smith \ / ) P.O. Box 1457 = Los Gatos, CA 95031-1457 _ / \ / \ _ TEL/FAX: 408-356-4186/358-3799 / /\ \ ] / /\ \ Mobile: 408-858-4528 | q-( ) | o |Email: d...@dsmith.org \ _ /]\ _ / Website: http://www.dsmith.org --- --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: R: Conducted Emissions on Telecom Ports
Actually it's to reduce interference to one's own equipment, (if it emits it - it's also susceptible to it). It also has the effect of reducing interference to other near by equipment. Michael Sundstrom Nokia Mobile Phones, PCC EMC Technician cube 4E : 390B phone: 972-374-1462 mobile: 817-917-5021 michael.sundst...@nokia.com amateur call: KB5UKT -Original Message- From: EXT Ken Javor [mailto:ken.ja...@emccompliance.com] Sent: Thursday, September 07, 2000 11:43 AM To: Paolo Roncone; 'eric.lif...@ni.com' Cc: 'emc-p...@ieee.org' Subject: Re: R: Conducted Emissions on Telecom Ports Although I don't work commercial EMC on a regular basis and I do not know over what frequency range the telecom port CE are controlled (I assume here 150 kHz - 30 MHz), I believe that there is a mistaken premise inherent in the comments to which I am responding. The purpose of controlling common mode CE on any port is not to protect equipment at the other end of the cable, or other co-sited cables, but rather to control radiated emissions in a frequency range in which CE are easier to measure than RE. In turn, the purpose of controlling RE is to protect broadcast radio reception. -- From: Paolo Roncone paolo.ronc...@compuprint.it To: 'eric.lif...@ni.com' eric.lif...@ni.com Cc: 'emc-p...@ieee.org' emc-p...@ieee.org Subject: R: Conducted Emissions on Telecom Ports Date: Thu, Sep 7, 2000, 9:45 AM Hi Eric, I 100% agree with you. The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. The problem is (as pointed out in one of the previous notes) that the new CISPR22 / EN55022 standard clearly includes LAN ports in the definition of telecommunications ports (section 3.6) no matter if they connect to the outside world or not. Regards, Paolo Roncone Compuprint s.p.a. Italy -Messaggio originale- Da: eric.lif...@ni.com [SMTP:eric.lif...@ni.com] Inviato: mercoledì 6 settembre 2000 17.55 A: emc-p...@ieee.org Oggetto: Re: Conducted Emissions on Telecom Ports All, As a not-quite-outside-observer (strictly EN 55011 here) of this thread, it's not fun seeing LAN ports classified as telecom; IMO that's overkill for the folks using EN 55022. Up till now, I considered a port to be telecom only if it connects a client facility to a carrier's network (DSL, ISDN, T1 and so on). With repeaters every 5 meters, USB and 1394 can support a bus long enough to connect between adjacent buildings. So, I wonder if some fanatic will soon be promoting USB/1394 ports as telecom? If Chris is right, and the EN 55022 version of the old telecom port conducted emission standard was intended to protect other telecom signals in a bundle, then I would think that this test is clearly redundant to the immunity tests (61000-4-6 and -4-3) that offer the needed protection from the other end. Does this emission requirement appear to be a waste of time and money to anyone else? Regards, Eric Lifsey Compliance Manager National Instruments Please respond to Chris Allen chris_al...@eur.3com.com To: Pryor McGinnis c...@prodigy.net cc: david_ster...@ademco.com, emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com, John Moore john_mo...@eur.3com.com (bcc: Eric Lifsey/AUS/NIC) Subject: Re: Conducted Emissions on Telecom Ports Pryor, Unfortunately, I don't think the definition is in question. It specifically states, that for the purposes of the standard, LANs are to be considered as telecomms ports as per section 3.6. It probably would have been less ambiguous if the standard defined Telecomms ports as Ports which are intended to be connected to the telecomms network OR LANs OR similar networks. As far as enforcement goes this will not change from the current method of enforcing compliance, primarily via the end user requesting DoCs and the relevent test data to back this document up. I believe the requirement goes back to a test that was performed under either VDE 0805 or 0806 (it was a long time ago that I had to perform the test). It was specifically aimed at unscreened cables over a certain length being placed in cable ducts and their impact on adjacent telecomms cables (if anybody remebers StarLan this was the product I was involved in). Chris. Pryor McGinnis c...@prodigy.net on 05/09/2000 20:54:51 Please respond to Pryor McGinnis c...@prodigy.net Sent by: Pryor McGinnis c...@prodigy.net To: david_ster...@ademco.com, emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com cc:(Chris Allen/GB/3Com) Subject: Re: Conducted Emissions on Telecom Ports I do not disagree with the positions posted on this subject. My question is how does the EU interpret and enforce this requirement/definition. Pryor - Original Message - From: david_ster...@ademco.com To: emc-p
RE: Conducted Emissions on Telecom Ports
Hello Paolo, Group, If any PC source creates a common mode current flowing through your LAN card, then into the UTP cable then this current will show up as conducted emission. Its not the data that radiates, it's noise from the PC board. As soon as the LAN cable gets long enough, it will radiate : that's the outside world in my humble opinion. Conducted emission does not have to stay conducted. This test is also to control low frequency ( 30 Mhz) radiated emissions. STP will fix that, if the RJ connector permits the shield to connect VERY WELL to the LAN's card bracket AND the bracket is WELL inserted in WELL constructed PC enclosure. Three conditions, of which most often at least one fails to be fully compliant in many STP networks. The dataflow of a CAT5 UTP cable WILL NOT contribute to any interference. if it did so, the card would not work. Data will arrive too distorted at the other side. Not even if it is running close to other wiring. The twisting effect will compensate for every mutual coupling in neighboring cables. (unless a CM current exists !) How do you think ADSL modems work on ordinary (often unshielded) phone cables (not even CAT 5). Or just plain old ISDN data over miles of phone wire without radiating. UTP will often get interfered however due to CM capacitive 50/60 Hz coupling (E-field) This drives the receiver out of it's common mode range ( or if transformer coupled, the CMMRR of it is too bad, effectively transferring CM voltage into DM voltage). STP will help here too (but better/cheaper solutions exist : personal experience!). Modern 100 MHZ LAN data transfer over a 2 wire non coaxial cable is real high Tec. A friend of my replaced a 5 meter CAT5 cable by 1 meter of ordinary telephone cable (twisted) It did not work. To my opinion, STP is not necessary and is often erroneously prescribed: a waist of money. Regards, Gert Gremmen, (Ing) ce-test, qualified testing === Web presence http://www.cetest.nl CE-shop http://www.cetest.nl/ce_shop.htm /-/ Compliance testing is our core business /-/ === -Original Message- From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf Of Paolo Roncone Sent: Thursday, September 07, 2000 4:45 PM To: 'eric.lif...@ni.com' Cc: 'emc-p...@ieee.org' Subject: R: Conducted Emissions on Telecom Ports Hi Eric, I 100% agree with you. The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. The problem is (as pointed out in one of the previous notes) that the new CISPR22 / EN55022 standard clearly includes LAN ports in the definition of telecommunications ports (section 3.6) no matter if they connect to the outside world or not. Regards, Paolo Roncone Compuprint s.p.a. Italy -Messaggio originale- Da: eric.lif...@ni.com [SMTP:eric.lif...@ni.com] Inviato: mercoledì 6 settembre 2000 17.55 A:emc-p...@ieee.org Oggetto: Re: Conducted Emissions on Telecom Ports All, As a not-quite-outside-observer (strictly EN 55011 here) of this thread, it's not fun seeing LAN ports classified as telecom; IMO that's overkill for the folks using EN 55022. Up till now, I considered a port to be telecom only if it connects a client facility to a carrier's network (DSL, ISDN, T1 and so on). With repeaters every 5 meters, USB and 1394 can support a bus long enough to connect between adjacent buildings. So, I wonder if some fanatic will soon be promoting USB/1394 ports as telecom? If Chris is right, and the EN 55022 version of the old telecom port conducted emission standard was intended to protect other telecom signals in a bundle, then I would think that this test is clearly redundant to the immunity tests (61000-4-6 and -4-3) that offer the needed protection from the other end. Does this emission requirement appear to be a waste of time and money to anyone else? Regards, Eric Lifsey Compliance Manager National Instruments Please respond to Chris Allen chris_al...@eur.3com.com To: Pryor McGinnis c...@prodigy.net cc: david_ster...@ademco.com, emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com, John Moore john_mo...@eur.3com.com (bcc: Eric Lifsey/AUS/NIC) Subject: Re: Conducted Emissions on Telecom Ports Pryor, Unfortunately, I don't think the definition is in question. It specifically states, that for the purposes of the standard, LANs are to be considered as telecomms ports as per section 3.6. It probably would have been less ambiguous if the standard defined Telecomms ports as Ports which are intended to be connected to the telecomms network OR LANs OR similar networks. As far as enforcement goes this will not change from the current method of enforcing compliance, primarily via the end user requesting DoCs and the relevent test data to back
RE: Conducted Emissions on Telecom Ports
For what it's worth: We bought a printer server made in France, it requires STP (shielded) cable for CE compliance. We use it to test our 10/100 Ethernet ports. So at least one French/EU entity believes in STP cable. I also have a small 4 port 10/100 hub at home, it requires STP to pass. Uh, I haven't bought any STP cable yet. :) I do have a little interesting EMI experience: I'm an amateur radio operator and have HF (1.8 to 30 MHz) equipment in my van. I am picking up noise every ~100 kHz or so in several bands, up to 15 dB above the noise floor, from a few meters outside my house. The regular pulsing noise is present even if the 10/100 Ethernet is idle (all computers off), but the Toshiba cable modem is always on. Cable modems uplink on 5 to 50 MHz, right through prime ham radio real estate. But, there could be other sources to blame, I'll find it when I get enough time Eric Lifsey Please respond to lfresea...@aol.com To: david_ster...@ademco.com, chris_al...@eur.3com.com, c...@prodigy.net, cet...@cetest.nl cc: emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com, john_mo...@eur.3com.com (bcc: Eric Lifsey/AUS/NIC) Subject: RE: Conducted Emissions on Telecom Ports Hi all, just thought I'd throw a few Euros in... First, until folks in the computer world know what shielded cable means ( anything less that 40 dB is lossy insulation;-))) ), I'd stear clear of specifying them. This is 20 years of experience talking, and shields seem to cause more problems ( 'cause they are missinstalled ) than they fix: right Ken J? Second, the probability of interference ( or immunity ) from LAN wiring depends a lot on where they are routed. If LAN wires are bundled with phone wires, interference will result... Conducted emissions control on LANs will minimize this. Remember, the LAN can act as a path for noise to leave the PC, it need not be direct LAN sourced noise! Poor layout of a LAN card causes this Third, I've tested a bunch of LAN cards from different folks There is a huge difference between vendors. Not all cards have the ability to terminate a shield properly. I would suggest that vendors comply with conducted limits deemed appropriate by the power that be, without applying any form of shielding. If you disagree with the powers that be, join the committee that develops the requiremnt in the first place! I say this as a LAN product end user... and someone active in the committees that write the requirements for my products. Thanks, Derek. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: R: Conducted Emissions on Telecom Ports
Has anyone seen problems with ethernet and conducted emissions? I have a home office with 4 PCs networked with ethernet running over UTP and I haven't seen much of a problem. Granted, the longest cable run I have is to a file server in the basement (about 10 meters) but both my AM radio and my shortwave set seem to work just fine. The only thing I remember picking up is 20MHz on the shortwave set. (Most 10Mbit ethernet devices use a 20MHz clock.) At work we have both 10 and 100Mbit ethernet (150-200 nodes) and the AM reception is really bad but I attribute that to the building (big steel and brick box) more than noise as reception improves as you get closer to a window. I haven't tried the shortwave at work being that shortwave reception is usually bad during the day anyway. As far as telephone lines are concerned my ears don't pick up much noise above 19kHz. I would think anything else would be covered by immunity standards. Steve -Original Message- From: Cortland Richmond [mailto:72146@compuserve.com] Sent: Thursday, September 07, 2000 11:01 AM To: Paolo Roncone; ieee pstc list Subject: Re: R: Conducted Emissions on Telecom Ports Paolo Roncone wrote: The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. I disagree. The purpose of emissions standards is to prevent interference. Some are to similar functions, some are to other media. There is no interface for interference at which point the manufacturer may say: Interference when you use this isn't our problem. We may say: Use shielded cable, or Put a ferrite on your cable, but we can't evade the physical fact that it is our own equipment which is the source of interference, and the cable is its antenna. It does not matter that we do not own the cable; if you plug it in and there is interference, it is up to the people who made the equipment to see the interference reduced. There is no transfer of ownership for radio waves. Granted, to call a LAN cable telecommunications is a clumsy construction of the regulation. But those who grasp at that straw to save a few currency units will find themselves later regretting that they have done so. If you are beaten and robbed for a display of wealth, it is no use protesting that the money was counterfeit. Cortland Richmond (I speak for myself alone and not for my employer) == Original Message Follows Date: 07-Sep-00 07:48:16 MsgID: 1072-46656 ToID: 72146,373 From: Paolo Roncone INTERNET:paolo.ronc...@compuprint.it Subj: R: Conducted Emissions on Telecom Ports Chrg: $0.00 Imp: Norm Sens: StdReceipt: NoParts: 1 From: Paolo Roncone paolo.ronc...@compuprint.it Subject: R: Conducted Emissions on Telecom Ports List-Post: emc-pstc@listserv.ieee.org Date: Thu, 7 Sep 2000 16:45:03 +0200 Reply-To: Paolo Roncone paolo.ronc...@compuprint.it Hi Eric, I 100% agree with you. The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. The problem is (as pointed out in one of the previous notes) that the new CISPR22 / EN55022 standard clearly includes LAN ports in the definition of telecommunications ports (section 3.6) no matter if they connect to the outside world or not. Regards, Paolo Roncone Compuprint s.p.a. Italy -Messaggio originale- Da: eric.lif...@ni.com [SMTP:eric.lif...@ni.com] Inviato:mercoledì 6 settembre 2000 17.55 A: emc-p...@ieee.org Oggetto:Re: Conducted Emissions on Telecom Ports All, As a not-quite-outside-observer (strictly EN 55011 here) of this thread, it's not fun seeing LAN ports classified as telecom; IMO that's overkill for the folks using EN 55022. Up till now, I considered a port to be telecom only if it connects a client facility to a carrier's network (DSL, ISDN, T1 and so on). With repeaters every 5 meters, USB and 1394 can support a bus long enough to connect between adjacent buildings. So, I wonder if some fanatic will soon be promoting USB/1394 ports as telecom? If Chris is right, and the EN 55022 version of the old telecom port conducted emission standard was intended to protect other telecom signals in a bundle, then I would think that this test is clearly redundant to the immunity tests (61000-4-6 and -4-3) that offer the needed protection from the other end. Does this emission requirement appear to be a waste of time and money to anyone else? Regards, Eric Lifsey Compliance Manager National Instruments Please respond to Chris Allen chris_al...@eur.3com.com To: Pryor McGinnis c...@prodigy.net cc: david_ster...@ademco.com, emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com, John Moore john_mo...@eur.3com.com (bcc: Eric Lifsey/AUS/NIC
RE: Conducted Emissions on Telecom Ports
Another little nagging problem exists. Without going into the whole historically precedence UTP was a pretty important reason why ethernet was adopted so widely. The wiring was pretty much in place because of the cables that had been run for connecting office telephones etc. People don't want to drag in new cables (STP) because of the cost. I happen to agree with you assements below and wouldn't even consider UTP if it weren't for the existing installs and the 805 standard that (prefers?) it. Thanks Gary -Original Message- From: david_ster...@ademco.com To: chris_al...@eur.3com.com; c...@prodigy.net; cet...@cetest.nl Cc: emc-p...@ieee.org; gary.mcintu...@worldwidepackets.com; john_mo...@eur.3com.com Sent: 9/7/00 6:09 AM Subject: RE: Conducted Emissions on Telecom Ports Hello Group, North America has likely the largest installed base of Ethernet, Fast-ethernet, Token-Ring and Arcnet in the world. STP cable is seldom installed (some use it for secure installations to inhibit listening devices). We have no complaints of interference with our TV or telephone systems. Grounding? I doubt if grounding problems are the culprit, since physical layer specifications define transformer isolation of STP cables. Certainly you can get coupling into long parallel runs of telephone and Arcnet (2.5 MHz), 10BaseT Ethernet (10 MHz) and Token-ring (4/16 MHz). The 125 MHz nominal of 100BaseTX lies above the EN55022 conducted emission band and the transient is lower so it can theoretically pass, however most cards auto-negotiate between 10BaseT and 100BaseTX. Connectivity Supposing your product manages to meet conducted emissions w/o STP, what does it connect with? The other end of the cable can connect to any compatible network product. If a PC hub or switch is relocated can a company replace UTP with STP? To protect the installation you must use STP everywhere. Therefore invoke the STP loophole. David Sterner ADEMCO Syosset NY __ Reply Separator _ Subject: RE: Conducted Emissions on Telecom Ports Author: Gert Gremmen SMTP:cet...@cetest.nl at ADEMCONET List-Post: emc-pstc@listserv.ieee.org Date:9/6/2000 2:53 PM Hello Group, From EMC emissions point of view, any cable connected to any device is prone to conducted emission problems. The is because grounding problems in a PCB exist or enclosure currents flow between shielded connectors. This leads to CM currents that will be measured. The criterion for testing is if any cable gets that long that frequencies below 30 Mhz can get out : l lambda/4 This requires cables to be longer than 2m50 at 30 Mhz to over 750 m at 150 KHz. This requirements is easily met by LAN and other ports. In the past no electrical equipment had any cable but the mains. The ITE equipment was recognized to have PSTN cables that long. Now antenna cables on Radio/TV gets the same treatment (and more) Cable television distribution system need conducted testing too. My opinion is that any network connection needs testing for Conducted emissions. In the case of the PC and the LAN card: definitely test. The attenuation of ground noise in any slot of the MB by the LAN card to the LAN cable, shielded or unshielded is unknown. In one MB it may pass, the other may fail. Regards, Gert Gremmen, (Ing) ce-test, qualified testing === Web presence http://www.cetest.nl CE-shop http://www.cetest.nl/ce_shop.htm /-/ Compliance testing is our core business /-/ === -Original Message- From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf Of Chris Allen Sent: Wednesday, September 06, 2000 10:40 AM To: Pryor McGinnis Cc: david_ster...@ademco.com; emc-p...@ieee.org; gary.mcintu...@worldwidepackets.com; John Moore Subject: Re: Conducted Emissions on Telecom Ports Pryor, Unfortunately, I don't think the definition is in question. It specifically states, that for the purposes of the standard, LANs are to be considered as telecomms ports as per section 3.6. It probably would have been less ambiguous if the standard defined Telecomms ports as Ports which are intended to be connected to the telecomms network OR LANs OR similar networks. As far as enforcement goes this will not change from the current method of enforcing compliance, primarily via the end user requesting DoCs and the relevent test data to back this document up. I believe the requirement goes back to a test that was performed under either VDE 0805 or 0806 (it was a long time ago that I had to perform the test). It was specifically aimed at unscreened cables over a certain length being placed in cable ducts
Re: R: Conducted Emissions on Telecom Ports
Although I don't work commercial EMC on a regular basis and I do not know over what frequency range the telecom port CE are controlled (I assume here 150 kHz - 30 MHz), I believe that there is a mistaken premise inherent in the comments to which I am responding. The purpose of controlling common mode CE on any port is not to protect equipment at the other end of the cable, or other co-sited cables, but rather to control radiated emissions in a frequency range in which CE are easier to measure than RE. In turn, the purpose of controlling RE is to protect broadcast radio reception. -- From: Paolo Roncone paolo.ronc...@compuprint.it To: 'eric.lif...@ni.com' eric.lif...@ni.com Cc: 'emc-p...@ieee.org' emc-p...@ieee.org Subject: R: Conducted Emissions on Telecom Ports Date: Thu, Sep 7, 2000, 9:45 AM Hi Eric, I 100% agree with you. The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. The problem is (as pointed out in one of the previous notes) that the new CISPR22 / EN55022 standard clearly includes LAN ports in the definition of telecommunications ports (section 3.6) no matter if they connect to the outside world or not. Regards, Paolo Roncone Compuprint s.p.a. Italy -Messaggio originale- Da: eric.lif...@ni.com [SMTP:eric.lif...@ni.com] Inviato: mercoledì 6 settembre 2000 17.55 A: emc-p...@ieee.org Oggetto: Re: Conducted Emissions on Telecom Ports All, As a not-quite-outside-observer (strictly EN 55011 here) of this thread, it's not fun seeing LAN ports classified as telecom; IMO that's overkill for the folks using EN 55022. Up till now, I considered a port to be telecom only if it connects a client facility to a carrier's network (DSL, ISDN, T1 and so on). With repeaters every 5 meters, USB and 1394 can support a bus long enough to connect between adjacent buildings. So, I wonder if some fanatic will soon be promoting USB/1394 ports as telecom? If Chris is right, and the EN 55022 version of the old telecom port conducted emission standard was intended to protect other telecom signals in a bundle, then I would think that this test is clearly redundant to the immunity tests (61000-4-6 and -4-3) that offer the needed protection from the other end. Does this emission requirement appear to be a waste of time and money to anyone else? Regards, Eric Lifsey Compliance Manager National Instruments Please respond to Chris Allen chris_al...@eur.3com.com To: Pryor McGinnis c...@prodigy.net cc: david_ster...@ademco.com, emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com, John Moore john_mo...@eur.3com.com (bcc: Eric Lifsey/AUS/NIC) Subject: Re: Conducted Emissions on Telecom Ports Pryor, Unfortunately, I don't think the definition is in question. It specifically states, that for the purposes of the standard, LANs are to be considered as telecomms ports as per section 3.6. It probably would have been less ambiguous if the standard defined Telecomms ports as Ports which are intended to be connected to the telecomms network OR LANs OR similar networks. As far as enforcement goes this will not change from the current method of enforcing compliance, primarily via the end user requesting DoCs and the relevent test data to back this document up. I believe the requirement goes back to a test that was performed under either VDE 0805 or 0806 (it was a long time ago that I had to perform the test). It was specifically aimed at unscreened cables over a certain length being placed in cable ducts and their impact on adjacent telecomms cables (if anybody remebers StarLan this was the product I was involved in). Chris. Pryor McGinnis c...@prodigy.net on 05/09/2000 20:54:51 Please respond to Pryor McGinnis c...@prodigy.net Sent by: Pryor McGinnis c...@prodigy.net To: david_ster...@ademco.com, emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com cc:(Chris Allen/GB/3Com) Subject: Re: Conducted Emissions on Telecom Ports I do not disagree with the positions posted on this subject. My question is how does the EU interpret and enforce this requirement/definition. Pryor - Original Message - From: david_ster...@ademco.com To: emc-p...@ieee.org; gary.mcintu...@worldwidepackets.com Sent: Tuesday, September 05, 2000 2:07 PM Subject: RE: Conducted Emissions on Telecom Ports LAN ports Testing Conducted RF Emissions on LAN twisted-pair lines is almost contrary to the intent of EN 55022 as Gary pointed out. Conducted emissions is more appropriate for asynchronous analog lines. LAN transmissions are digital and synchronous (except maybe ATM); the receiver part of the interface circuitry locks onto the frequency of data, rejecting spurious frequencies. The signals are truely digital
RE: Conducted Emissions on Telecom Ports
Hi all, just thought I'd throw a few Euros in... First, until folks in the computer world know what shielded cable means ( anything less that 40 dB is lossy insulation;-))) ), I'd stear clear of specifying them. This is 20 years of experience talking, and shields seem to cause more problems ( 'cause they are missinstalled ) than they fix: right Ken J? Second, the probability of interference ( or immunity ) from LAN wiring depends a lot on where they are routed. If LAN wires are bundled with phone wires, interference will result... Conducted emissions control on LANs will minimize this. Remember, the LAN can act as a path for noise to leave the PC, it need not be direct LAN sourced noise! Poor layout of a LAN card causes this Third, I've tested a bunch of LAN cards from different folks There is a huge difference between vendors. Not all cards have the ability to terminate a shield properly. I would suggest that vendors comply with conducted limits deemed appropriate by the power that be, without applying any form of shielding. If you disagree with the powers that be, join the committee that develops the requiremnt in the first place! I say this as a LAN product end user... and someone active in the committees that write the requirements for my products. Thanks, Derek. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: R: Conducted Emissions on Telecom Ports
Paolo Roncone wrote: The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. I disagree. The purpose of emissions standards is to prevent interference. Some are to similar functions, some are to other media. There is no interface for interference at which point the manufacturer may say: Interference when you use this isn't our problem. We may say: Use shielded cable, or Put a ferrite on your cable, but we can't evade the physical fact that it is our own equipment which is the source of interference, and the cable is its antenna. It does not matter that we do not own the cable; if you plug it in and there is interference, it is up to the people who made the equipment to see the interference reduced. There is no transfer of ownership for radio waves. Granted, to call a LAN cable telecommunications is a clumsy construction of the regulation. But those who grasp at that straw to save a few currency units will find themselves later regretting that they have done so. If you are beaten and robbed for a display of wealth, it is no use protesting that the money was counterfeit. Cortland Richmond (I speak for myself alone and not for my employer) == Original Message Follows Date: 07-Sep-00 07:48:16 MsgID: 1072-46656 ToID: 72146,373 From: Paolo Roncone INTERNET:paolo.ronc...@compuprint.it Subj: R: Conducted Emissions on Telecom Ports Chrg: $0.00 Imp: Norm Sens: StdReceipt: NoParts: 1 From: Paolo Roncone paolo.ronc...@compuprint.it Subject: R: Conducted Emissions on Telecom Ports List-Post: emc-pstc@listserv.ieee.org Date: Thu, 7 Sep 2000 16:45:03 +0200 Reply-To: Paolo Roncone paolo.ronc...@compuprint.it Hi Eric, I 100% agree with you. The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. The problem is (as pointed out in one of the previous notes) that the new CISPR22 / EN55022 standard clearly includes LAN ports in the definition of telecommunications ports (section 3.6) no matter if they connect to the outside world or not. Regards, Paolo Roncone Compuprint s.p.a. Italy -Messaggio originale- Da: eric.lif...@ni.com [SMTP:eric.lif...@ni.com] Inviato:mercoledì 6 settembre 2000 17.55 A: emc-p...@ieee.org Oggetto:Re: Conducted Emissions on Telecom Ports All, As a not-quite-outside-observer (strictly EN 55011 here) of this thread, it's not fun seeing LAN ports classified as telecom; IMO that's overkill for the folks using EN 55022. Up till now, I considered a port to be telecom only if it connects a client facility to a carrier's network (DSL, ISDN, T1 and so on). With repeaters every 5 meters, USB and 1394 can support a bus long enough to connect between adjacent buildings. So, I wonder if some fanatic will soon be promoting USB/1394 ports as telecom? If Chris is right, and the EN 55022 version of the old telecom port conducted emission standard was intended to protect other telecom signals in a bundle, then I would think that this test is clearly redundant to the immunity tests (61000-4-6 and -4-3) that offer the needed protection from the other end. Does this emission requirement appear to be a waste of time and money to anyone else? Regards, Eric Lifsey Compliance Manager National Instruments Please respond to Chris Allen chris_al...@eur.3com.com To: Pryor McGinnis c...@prodigy.net cc: david_ster...@ademco.com, emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com, John Moore john_mo...@eur.3com.com (bcc: Eric Lifsey/AUS/NIC) Subject: Re: Conducted Emissions on Telecom Ports Pryor, Unfortunately, I don't think the definition is in question. It specifically states, that for the purposes of the standard, LANs are to be considered as telecomms ports as per section 3.6. It probably would have been less ambiguous if the standard defined Telecomms ports as Ports which are intended to be connected to the telecomms network OR LANs OR similar networks. As far as enforcement goes this will not change from the current method of enforcing compliance, primarily via the end user requesting DoCs and the relevent test data to back this document up. I believe the requirement goes back to a test that was performed under either VDE 0805 or 0806 (it was a long time ago that I had to perform the test). It was specifically aimed at unscreened cables over a certain length being placed in cable ducts and their impact on adjacent telecomms cables (if anybody remebers StarLan this was the product I was involved in). Chris. Pryor McGinnis c...@prodigy.net on 05/09/2000 20:54:51 Please respond to Pryor McGinnis c...@prodigy.net Sent by: Pryor McGinnis c...@prodigy.net To: david_ster
R: Conducted Emissions on Telecom Ports
Hi Eric, I 100% agree with you. The scope of emissions standard should be to protect the outside (i.e. public) environment from interference. So only ports that connect to public telecom networks should be covered by the standard. The problem is (as pointed out in one of the previous notes) that the new CISPR22 / EN55022 standard clearly includes LAN ports in the definition of telecommunications ports (section 3.6) no matter if they connect to the outside world or not. Regards, Paolo Roncone Compuprint s.p.a. Italy -Messaggio originale- Da: eric.lif...@ni.com [SMTP:eric.lif...@ni.com] Inviato:mercoledì 6 settembre 2000 17.55 A: emc-p...@ieee.org Oggetto:Re: Conducted Emissions on Telecom Ports All, As a not-quite-outside-observer (strictly EN 55011 here) of this thread, it's not fun seeing LAN ports classified as telecom; IMO that's overkill for the folks using EN 55022. Up till now, I considered a port to be telecom only if it connects a client facility to a carrier's network (DSL, ISDN, T1 and so on). With repeaters every 5 meters, USB and 1394 can support a bus long enough to connect between adjacent buildings. So, I wonder if some fanatic will soon be promoting USB/1394 ports as telecom? If Chris is right, and the EN 55022 version of the old telecom port conducted emission standard was intended to protect other telecom signals in a bundle, then I would think that this test is clearly redundant to the immunity tests (61000-4-6 and -4-3) that offer the needed protection from the other end. Does this emission requirement appear to be a waste of time and money to anyone else? Regards, Eric Lifsey Compliance Manager National Instruments Please respond to Chris Allen chris_al...@eur.3com.com To: Pryor McGinnis c...@prodigy.net cc: david_ster...@ademco.com, emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com, John Moore john_mo...@eur.3com.com (bcc: Eric Lifsey/AUS/NIC) Subject: Re: Conducted Emissions on Telecom Ports Pryor, Unfortunately, I don't think the definition is in question. It specifically states, that for the purposes of the standard, LANs are to be considered as telecomms ports as per section 3.6. It probably would have been less ambiguous if the standard defined Telecomms ports as Ports which are intended to be connected to the telecomms network OR LANs OR similar networks. As far as enforcement goes this will not change from the current method of enforcing compliance, primarily via the end user requesting DoCs and the relevent test data to back this document up. I believe the requirement goes back to a test that was performed under either VDE 0805 or 0806 (it was a long time ago that I had to perform the test). It was specifically aimed at unscreened cables over a certain length being placed in cable ducts and their impact on adjacent telecomms cables (if anybody remebers StarLan this was the product I was involved in). Chris. Pryor McGinnis c...@prodigy.net on 05/09/2000 20:54:51 Please respond to Pryor McGinnis c...@prodigy.net Sent by: Pryor McGinnis c...@prodigy.net To: david_ster...@ademco.com, emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com cc:(Chris Allen/GB/3Com) Subject: Re: Conducted Emissions on Telecom Ports I do not disagree with the positions posted on this subject. My question is how does the EU interpret and enforce this requirement/definition. Pryor - Original Message - From: david_ster...@ademco.com To: emc-p...@ieee.org; gary.mcintu...@worldwidepackets.com Sent: Tuesday, September 05, 2000 2:07 PM Subject: RE: Conducted Emissions on Telecom Ports LAN ports Testing Conducted RF Emissions on LAN twisted-pair lines is almost contrary to the intent of EN 55022 as Gary pointed out. Conducted emissions is more appropriate for asynchronous analog lines. LAN transmissions are digital and synchronous (except maybe ATM); the receiver part of the interface circuitry locks onto the frequency of data, rejecting spurious frequencies. The signals are truely digital, not analog as in a modem. Arcnet, Ethernet, and Fast Ethernet TP cabling links two points (node, hub, switch, bridge) which digitally reconstitute the signal, eliminating spurious cable frequencies. Token-Ring is peer-peer, usually through a passive hub. Each node (peer) reconstitutes the signal as above. Ethernet, F-E and Token-Ring ANSI/IEEE or ISO/IEC physical layer requirements define interfaces, cable lengths/type(s) and timing. Coax cable rules for Arcnet, 10Base2 Ethernet) permit connection to multiple nodes but again, the digital nature of the signals and the well-defined connectivity rules prevent problems. David __ Reply Separator _ Subject: RE: Conducted Emissions on Telecom Ports
RE: Conducted Emissions on Telecom Ports
Hello Group, North America has likely the largest installed base of Ethernet, Fast-ethernet, Token-Ring and Arcnet in the world. STP cable is seldom installed (some use it for secure installations to inhibit listening devices). We have no complaints of interference with our TV or telephone systems. Grounding? I doubt if grounding problems are the culprit, since physical layer specifications define transformer isolation of STP cables. Certainly you can get coupling into long parallel runs of telephone and Arcnet (2.5 MHz), 10BaseT Ethernet (10 MHz) and Token-ring (4/16 MHz). The 125 MHz nominal of 100BaseTX lies above the EN55022 conducted emission band and the transient is lower so it can theoretically pass, however most cards auto-negotiate between 10BaseT and 100BaseTX. Connectivity Supposing your product manages to meet conducted emissions w/o STP, what does it connect with? The other end of the cable can connect to any compatible network product. If a PC hub or switch is relocated can a company replace UTP with STP? To protect the installation you must use STP everywhere. Therefore invoke the STP loophole. David Sterner ADEMCO Syosset NY __ Reply Separator _ Subject: RE: Conducted Emissions on Telecom Ports Author: Gert Gremmen SMTP:cet...@cetest.nl at ADEMCONET List-Post: emc-pstc@listserv.ieee.org Date:9/6/2000 2:53 PM Hello Group, From EMC emissions point of view, any cable connected to any device is prone to conducted emission problems. The is because grounding problems in a PCB exist or enclosure currents flow between shielded connectors. This leads to CM currents that will be measured. The criterion for testing is if any cable gets that long that frequencies below 30 Mhz can get out : l lambda/4 This requires cables to be longer than 2m50 at 30 Mhz to over 750 m at 150 KHz. This requirements is easily met by LAN and other ports. In the past no electrical equipment had any cable but the mains. The ITE equipment was recognized to have PSTN cables that long. Now antenna cables on Radio/TV gets the same treatment (and more) Cable television distribution system need conducted testing too. My opinion is that any network connection needs testing for Conducted emissions. In the case of the PC and the LAN card: definitely test. The attenuation of ground noise in any slot of the MB by the LAN card to the LAN cable, shielded or unshielded is unknown. In one MB it may pass, the other may fail. Regards, Gert Gremmen, (Ing) ce-test, qualified testing === Web presence http://www.cetest.nl CE-shop http://www.cetest.nl/ce_shop.htm /-/ Compliance testing is our core business /-/ === -Original Message- From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf Of Chris Allen Sent: Wednesday, September 06, 2000 10:40 AM To: Pryor McGinnis Cc: david_ster...@ademco.com; emc-p...@ieee.org; gary.mcintu...@worldwidepackets.com; John Moore Subject: Re: Conducted Emissions on Telecom Ports Pryor, Unfortunately, I don't think the definition is in question. It specifically states, that for the purposes of the standard, LANs are to be considered as telecomms ports as per section 3.6. It probably would have been less ambiguous if the standard defined Telecomms ports as Ports which are intended to be connected to the telecomms network OR LANs OR similar networks. As far as enforcement goes this will not change from the current method of enforcing compliance, primarily via the end user requesting DoCs and the relevent test data to back this document up. I believe the requirement goes back to a test that was performed under either VDE 0805 or 0806 (it was a long time ago that I had to perform the test). It was specifically aimed at unscreened cables over a certain length being placed in cable ducts and their impact on adjacent telecomms cables (if anybody remebers StarLan this was the product I was involved in). Chris. Pryor McGinnis c...@prodigy.net on 05/09/2000 20:54:51 Please respond to Pryor McGinnis c...@prodigy.net Sent by: Pryor McGinnis c...@prodigy.net To: david_ster...@ademco.com, emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com cc:(Chris Allen/GB/3Com) Subject: Re: Conducted Emissions on Telecom Ports I do not disagree with the positions posted on this subject. My question is how does the EU interpret and enforce this requirement/definition. Pryor - Original Message - From: david_ster...@ademco.com To: emc-p...@ieee.org; gary.mcintu...@worldwidepackets.com Sent: Tuesday, September 05, 2000 2:07 PM Subject: RE
RE: Conducted Emissions on Telecom Ports
Hello Group, From EMC emissions point of view, any cable connected to any device is prone to conducted emission problems. The is because grounding problems in a PCB exist or enclosure currents flow between shielded connectors. This leads to CM currents that will be measured. The criterion for testing is if any cable gets that long that frequencies below 30 Mhz can get out : l lambda/4 This requires cables to be longer than 2m50 at 30 Mhz to over 750 m at 150 KHz. This requirements is easily met by LAN and other ports. In the past no electrical equipment had any cable but the mains. The ITE equipment was recognized to have PSTN cables that long. Now antenna cables on Radio/TV gets the same treatment (and more) Cable television distribution system need conducted testing too. My opinion is that any network connection needs testing for Conducted emissions. In the case of the PC and the LAN card: definitely test. The attenuation of ground noise in any slot of the MB by the LAN card to the LAN cable, shielded or unshielded is unknown. In one MB it may pass, the other may fail. Regards, Gert Gremmen, (Ing) ce-test, qualified testing === Web presence http://www.cetest.nl CE-shop http://www.cetest.nl/ce_shop.htm /-/ Compliance testing is our core business /-/ === -Original Message- From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf Of Chris Allen Sent: Wednesday, September 06, 2000 10:40 AM To: Pryor McGinnis Cc: david_ster...@ademco.com; emc-p...@ieee.org; gary.mcintu...@worldwidepackets.com; John Moore Subject: Re: Conducted Emissions on Telecom Ports Pryor, Unfortunately, I don't think the definition is in question. It specifically states, that for the purposes of the standard, LANs are to be considered as telecomms ports as per section 3.6. It probably would have been less ambiguous if the standard defined Telecomms ports as Ports which are intended to be connected to the telecomms network OR LANs OR similar networks. As far as enforcement goes this will not change from the current method of enforcing compliance, primarily via the end user requesting DoCs and the relevent test data to back this document up. I believe the requirement goes back to a test that was performed under either VDE 0805 or 0806 (it was a long time ago that I had to perform the test). It was specifically aimed at unscreened cables over a certain length being placed in cable ducts and their impact on adjacent telecomms cables (if anybody remebers StarLan this was the product I was involved in). Chris. Pryor McGinnis c...@prodigy.net on 05/09/2000 20:54:51 Please respond to Pryor McGinnis c...@prodigy.net Sent by: Pryor McGinnis c...@prodigy.net To: david_ster...@ademco.com, emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com cc:(Chris Allen/GB/3Com) Subject: Re: Conducted Emissions on Telecom Ports I do not disagree with the positions posted on this subject. My question is how does the EU interpret and enforce this requirement/definition. Pryor - Original Message - From: david_ster...@ademco.com To: emc-p...@ieee.org; gary.mcintu...@worldwidepackets.com Sent: Tuesday, September 05, 2000 2:07 PM Subject: RE: Conducted Emissions on Telecom Ports LAN ports Testing Conducted RF Emissions on LAN twisted-pair lines is almost contrary to the intent of EN 55022 as Gary pointed out. Conducted emissions is more appropriate for asynchronous analog lines. LAN transmissions are digital and synchronous (except maybe ATM); the receiver part of the interface circuitry locks onto the frequency of data, rejecting spurious frequencies. The signals are truely digital, not analog as in a modem. Arcnet, Ethernet, and Fast Ethernet TP cabling links two points (node, hub, switch, bridge) which digitally reconstitute the signal, eliminating spurious cable frequencies. Token-Ring is peer-peer, usually through a passive hub. Each node (peer) reconstitutes the signal as above. Ethernet, F-E and Token-Ring ANSI/IEEE or ISO/IEC physical layer requirements define interfaces, cable lengths/type(s) and timing. Coax cable rules for Arcnet, 10Base2 Ethernet) permit connection to multiple nodes but again, the digital nature of the signals and the well-defined connectivity rules prevent problems. David __ Reply Separator _ Subject: RE: Conducted Emissions on Telecom Ports Author: Gary McInturff SMTP:gary.mcintu...@worldwidepackets.com at ADEMCONET Date:9/5/2000 10:54 AM Define telecom port. A LAN port isn't neccessarily a LAN port. Ethernet ports do not connect directly to the Telecommunications network - a necessary condition before being a telecommunications port. LANS
Re: Conducted Emissions on Telecom Ports
Pryor, Unfortunately, I don't think the definition is in question. It specifically states, that for the purposes of the standard, LANs are to be considered as telecomms ports as per section 3.6. It probably would have been less ambiguous if the standard defined Telecomms ports as Ports which are intended to be connected to the telecomms network OR LANs OR similar networks. As far as enforcement goes this will not change from the current method of enforcing compliance, primarily via the end user requesting DoCs and the relevent test data to back this document up. I believe the requirement goes back to a test that was performed under either VDE 0805 or 0806 (it was a long time ago that I had to perform the test). It was specifically aimed at unscreened cables over a certain length being placed in cable ducts and their impact on adjacent telecomms cables (if anybody remebers StarLan this was the product I was involved in). Chris. Pryor McGinnis c...@prodigy.net on 05/09/2000 20:54:51 Please respond to Pryor McGinnis c...@prodigy.net Sent by: Pryor McGinnis c...@prodigy.net To: david_ster...@ademco.com, emc-p...@ieee.org, gary.mcintu...@worldwidepackets.com cc:(Chris Allen/GB/3Com) Subject: Re: Conducted Emissions on Telecom Ports I do not disagree with the positions posted on this subject. My question is how does the EU interpret and enforce this requirement/definition. Pryor - Original Message - From: david_ster...@ademco.com To: emc-p...@ieee.org; gary.mcintu...@worldwidepackets.com Sent: Tuesday, September 05, 2000 2:07 PM Subject: RE: Conducted Emissions on Telecom Ports LAN ports Testing Conducted RF Emissions on LAN twisted-pair lines is almost contrary to the intent of EN 55022 as Gary pointed out. Conducted emissions is more appropriate for asynchronous analog lines. LAN transmissions are digital and synchronous (except maybe ATM); the receiver part of the interface circuitry locks onto the frequency of data, rejecting spurious frequencies. The signals are truely digital, not analog as in a modem. Arcnet, Ethernet, and Fast Ethernet TP cabling links two points (node, hub, switch, bridge) which digitally reconstitute the signal, eliminating spurious cable frequencies. Token-Ring is peer-peer, usually through a passive hub. Each node (peer) reconstitutes the signal as above. Ethernet, F-E and Token-Ring ANSI/IEEE or ISO/IEC physical layer requirements define interfaces, cable lengths/type(s) and timing. Coax cable rules for Arcnet, 10Base2 Ethernet) permit connection to multiple nodes but again, the digital nature of the signals and the well-defined connectivity rules prevent problems. David __ Reply Separator _ Subject: RE: Conducted Emissions on Telecom Ports Author: Gary McInturff SMTP:gary.mcintu...@worldwidepackets.com at ADEMCONET Date:9/5/2000 10:54 AM Define telecom port. A LAN port isn't neccessarily a LAN port. Ethernet ports do not connect directly to the Telecommunications network - a necessary condition before being a telecommunications port. LANS and MANS operate all of the time without any use of any telecommunications equipment. Generally, Ethernet or Fast Ethernet for short distances and Gig Ethernet for longer distances. IF -- the telecommunications lines are needed there is some sort of bridge that takes the ethernet and its digitized Voice over Internet Protocol (Voip) and does all of the phone stuff and makes the actual metallic connection. That birdge has the only telecommunication ports on it. Gary -Original Message- From: Pryor McGinnis [mailto:c...@prodigy.net] Sent: Thursday, August 31, 2000 6:24 AM To: Pettit, Ghery; david_ster...@ademco.com; emc-p...@ieee.org Subject: Re: Conducted Emissions on Telecom Ports Confusing isn't? - Original Message - From: Pettit, Ghery ghery.pet...@intel.com To: david_ster...@ademco.com; emc-p...@ieee.org; c...@prodigy.net Sent: Wednesday, August 30, 2000 5:40 PM Subject: RE: Conducted Emissions on Telecom Ports Actually, it's August 1, 2001 as posted in the OJ on January 25th of this year. You've got 1 less month to start testing to the new standard. Ghery Pettit Intel -Original Message- From: david_ster...@ademco.com [mailto:david_ster...@ademco.com] Sent: Wednesday, August 30, 2000 2:04 PM To: emc-p...@ieee.org; c...@prodigy.net Subject: RE: Conducted Emissions on Telecom Ports The date of withdrawal of EN 55022:1998 is September 1, 2001. Look at the NIC manual's DofC --- the mfgr. may not be declaring compliance to conducted emissions yet. __ Reply Separator _ Subject: Re: Conducted Emissions
RE: Conducted Emissions on Telecom Ports
If LAN's cause interference, the mechanism would be radiated, not conducted. Testing may be moot on LAN's whose fundimental frequency lies between 150kHz and 100MHz; STP is the only way to 'pass'. Of course STP has safety implications due to earthing potentials. David __ Reply Separator _ Subject: RE: Conducted Emissions on Telecom Ports Author: Mowbray; John H SMTP:jm134...@exchange.canada.ncr.com at ADEMCONET List-Post: emc-pstc@listserv.ieee.org Date:9/5/2000 12:06 PM Gary If you read the definition of telecomm ports in CISPR 22 (sect. 3.6) it includes Local Area Networks, and other similar networks. Some people have even tried to extend this to RS 232 because of past abuses of this interface (like stretching the cable length to several hundred feet). There is a great concern in some European Countries that LAN cables can cause interference. John Mowbray -Original Message- From: Gary McInturff [SMTP:gary.mcintu...@worldwidepackets.com] Sent: Tuesday, September 05, 2000 10:55 AM To: 'Pryor McGinnis'; Pettit, Ghery; david_ster...@ademco.com; emc-p...@ieee.org Subject: RE: Conducted Emissions on Telecom Ports Define telecom port. A LAN port isn't neccessarily a LAN port. Ethernet ports do not connect directly to the Telecommunications network - a necessary condition before being a telecommunications port. LANS and MANS operate all of the time without any use of any telecommunications equipment. Generally, Ethernet or Fast Ethernet for short distances and Gig Ethernet for longer distances. IF -- the telecommunications lines are needed there is some sort of bridge that takes the ethernet and its digitized Voice over Internet Protocol (Voip) and does all of the phone stuff and makes the actual metallic connection. That birdge has the only telecommunication ports on it. Gary -Original Message- From: Pryor McGinnis [mailto:c...@prodigy.net] Sent: Thursday, August 31, 2000 6:24 AM To: Pettit, Ghery; david_ster...@ademco.com; emc-p...@ieee.org Subject: Re: Conducted Emissions on Telecom Ports Confusing isn't? - Original Message - From: Pettit, Ghery ghery.pet...@intel.com To: david_ster...@ademco.com; emc-p...@ieee.org; c...@prodigy.net Sent: Wednesday, August 30, 2000 5:40 PM Subject: RE: Conducted Emissions on Telecom Ports Actually, it's August 1, 2001 as posted in the OJ on January 25th of this year. You've got 1 less month to start testing to the new standard. Ghery Pettit Intel -Original Message- From: david_ster...@ademco.com [mailto:david_ster...@ademco.com] Sent: Wednesday, August 30, 2000 2:04 PM To: emc-p...@ieee.org; c...@prodigy.net Subject: RE: Conducted Emissions on Telecom Ports The date of withdrawal of EN 55022:1998 is September 1, 2001. Look at the NIC manual's DofC --- the mfgr. may not be declaring compliance to conducted emissions yet. __ Reply Separator _ Subject: Re: Conducted Emissions on Telecom Ports Author: Pryor McGinnis SMTP:c...@prodigy.net at ADEMCONET Date:8/30/2000 10:31 AM Hello All, The question originated from a manufacturer of LAN boards who sells to end users and to manufacturer's who integrate the LAN boards into end products. I advised the LAN board manufacturer that conducted emissions would be required (with boards installed in typical host) on all LAN boards sold to end users and manufacturers of products that integrated LAN boards should test the ports for conducted emission in their end product. The LAN board manufacturer questioned double testing of the LAN boards. His concern is that boards that pass CE in a typical host may not pass in another manufacturer's end product (rub of the green). The LAN Board manufacturer ask for second opinions. Many thanks for your answers. Best Regards, Pryor -Original Message- From: Pryor McGinnis [SMTP:c...@prodigy.net] Sent: Tuesday, August 29, 2000 12:35 PM To: emc-pstc Subject: Conducted Emissions on Telecom Ports Below is a message from a non emc-pstc member. If a manufacturer purchases LAN boards which have been tested for conducted emissions in a host, is the manufacturer required to retest the LAN Ports for conducted emissions if the manufacturer sells his
RE: Conducted Emissions on Telecom Ports
LAN ports Testing Conducted RF Emissions on LAN twisted-pair lines is almost contrary to the intent of EN 55022 as Gary pointed out. Conducted emissions is more appropriate for asynchronous analog lines. LAN transmissions are digital and synchronous (except maybe ATM); the receiver part of the interface circuitry locks onto the frequency of data, rejecting spurious frequencies. The signals are truely digital, not analog as in a modem. Arcnet, Ethernet, and Fast Ethernet TP cabling links two points (node, hub, switch, bridge) which digitally reconstitute the signal, eliminating spurious cable frequencies. Token-Ring is peer-peer, usually through a passive hub. Each node (peer) reconstitutes the signal as above. Ethernet, F-E and Token-Ring ANSI/IEEE or ISO/IEC physical layer requirements define interfaces, cable lengths/type(s) and timing. Coax cable rules for Arcnet, 10Base2 Ethernet) permit connection to multiple nodes but again, the digital nature of the signals and the well-defined connectivity rules prevent problems. David __ Reply Separator _ Subject: RE: Conducted Emissions on Telecom Ports Author: Gary McInturff SMTP:gary.mcintu...@worldwidepackets.com at ADEMCONET List-Post: emc-pstc@listserv.ieee.org Date:9/5/2000 10:54 AM Define telecom port. A LAN port isn't neccessarily a LAN port. Ethernet ports do not connect directly to the Telecommunications network - a necessary condition before being a telecommunications port. LANS and MANS operate all of the time without any use of any telecommunications equipment. Generally, Ethernet or Fast Ethernet for short distances and Gig Ethernet for longer distances. IF -- the telecommunications lines are needed there is some sort of bridge that takes the ethernet and its digitized Voice over Internet Protocol (Voip) and does all of the phone stuff and makes the actual metallic connection. That birdge has the only telecommunication ports on it. Gary -Original Message- From: Pryor McGinnis [mailto:c...@prodigy.net] Sent: Thursday, August 31, 2000 6:24 AM To: Pettit, Ghery; david_ster...@ademco.com; emc-p...@ieee.org Subject: Re: Conducted Emissions on Telecom Ports Confusing isn't? - Original Message - From: Pettit, Ghery ghery.pet...@intel.com To: david_ster...@ademco.com; emc-p...@ieee.org; c...@prodigy.net Sent: Wednesday, August 30, 2000 5:40 PM Subject: RE: Conducted Emissions on Telecom Ports Actually, it's August 1, 2001 as posted in the OJ on January 25th of this year. You've got 1 less month to start testing to the new standard. Ghery Pettit Intel -Original Message- From: david_ster...@ademco.com [mailto:david_ster...@ademco.com] Sent: Wednesday, August 30, 2000 2:04 PM To: emc-p...@ieee.org; c...@prodigy.net Subject: RE: Conducted Emissions on Telecom Ports The date of withdrawal of EN 55022:1998 is September 1, 2001. Look at the NIC manual's DofC --- the mfgr. may not be declaring compliance to conducted emissions yet. __ Reply Separator _ Subject: Re: Conducted Emissions on Telecom Ports Author: Pryor McGinnis SMTP:c...@prodigy.net at ADEMCONET Date:8/30/2000 10:31 AM Hello All, The question originated from a manufacturer of LAN boards who sells to end users and to manufacturer's who integrate the LAN boards into end products. I advised the LAN board manufacturer that conducted emissions would be required (with boards installed in typical host) on all LAN boards sold to end users and manufacturers of products that integrated LAN boards should test the ports for conducted emission in their end product. The LAN board manufacturer questioned double testing of the LAN boards. His concern is that boards that pass CE in a typical host may not pass in another manufacturer's end product (rub of the green). The LAN Board manufacturer ask for second opinions. Many thanks for your answers. Best Regards, Pryor -Original Message- From: Pryor McGinnis [SMTP:c...@prodigy.net] Sent: Tuesday, August 29, 2000 12:35 PM To: emc-pstc Subject: Conducted Emissions on Telecom Ports Below is a message from a non emc-pstc member. If a manufacturer purchases LAN boards which have been tested for conducted emissions in a host, is the manufacturer required to retest the LAN Ports for conducted emissions if the manufacturer sells his product with the LAN board installed? I am very interested in your comments. Best Regards, Pryor McGinnis c...@prodigy.net mailto:c...@prodigy.net www.ctl-lab.com http://www.ctl-lab.com
RE: Conducted Emissions on Telecom Ports
Gary If you read the definition of telecomm ports in CISPR 22 (sect. 3.6) it includes Local Area Networks, and other similar networks. Some people have even tried to extend this to RS 232 because of past abuses of this interface (like stretching the cable length to several hundred feet). There is a great concern in some European Countries that LAN cables can cause interference. John Mowbray -Original Message- From: Gary McInturff [SMTP:gary.mcintu...@worldwidepackets.com] Sent: Tuesday, September 05, 2000 10:55 AM To: 'Pryor McGinnis'; Pettit, Ghery; david_ster...@ademco.com; emc-p...@ieee.org Subject:RE: Conducted Emissions on Telecom Ports Define telecom port. A LAN port isn't neccessarily a LAN port. Ethernet ports do not connect directly to the Telecommunications network - a necessary condition before being a telecommunications port. LANS and MANS operate all of the time without any use of any telecommunications equipment. Generally, Ethernet or Fast Ethernet for short distances and Gig Ethernet for longer distances. IF -- the telecommunications lines are needed there is some sort of bridge that takes the ethernet and its digitized Voice over Internet Protocol (Voip) and does all of the phone stuff and makes the actual metallic connection. That birdge has the only telecommunication ports on it. Gary -Original Message- From: Pryor McGinnis [mailto:c...@prodigy.net] Sent: Thursday, August 31, 2000 6:24 AM To: Pettit, Ghery; david_ster...@ademco.com; emc-p...@ieee.org Subject: Re: Conducted Emissions on Telecom Ports Confusing isn't? - Original Message - From: Pettit, Ghery ghery.pet...@intel.com To: david_ster...@ademco.com; emc-p...@ieee.org; c...@prodigy.net Sent: Wednesday, August 30, 2000 5:40 PM Subject: RE: Conducted Emissions on Telecom Ports Actually, it's August 1, 2001 as posted in the OJ on January 25th of this year. You've got 1 less month to start testing to the new standard. Ghery Pettit Intel -Original Message- From: david_ster...@ademco.com [mailto:david_ster...@ademco.com] Sent: Wednesday, August 30, 2000 2:04 PM To: emc-p...@ieee.org; c...@prodigy.net Subject: RE: Conducted Emissions on Telecom Ports The date of withdrawal of EN 55022:1998 is September 1, 2001. Look at the NIC manual's DofC --- the mfgr. may not be declaring compliance to conducted emissions yet. __ Reply Separator _ Subject: Re: Conducted Emissions on Telecom Ports Author: Pryor McGinnis SMTP:c...@prodigy.net at ADEMCONET Date:8/30/2000 10:31 AM Hello All, The question originated from a manufacturer of LAN boards who sells to end users and to manufacturer's who integrate the LAN boards into end products. I advised the LAN board manufacturer that conducted emissions would be required (with boards installed in typical host) on all LAN boards sold to end users and manufacturers of products that integrated LAN boards should test the ports for conducted emission in their end product. The LAN board manufacturer questioned double testing of the LAN boards. His concern is that boards that pass CE in a typical host may not pass in another manufacturer's end product (rub of the green). The LAN Board manufacturer ask for second opinions. Many thanks for your answers. Best Regards, Pryor -Original Message- From: Pryor McGinnis [SMTP:c...@prodigy.net] Sent: Tuesday, August 29, 2000 12:35 PM To: emc-pstc Subject: Conducted Emissions on Telecom Ports Below is a message from a non emc-pstc member. If a manufacturer purchases LAN boards which have been tested for conducted emissions in a host, is the manufacturer required to retest the LAN Ports for conducted emissions if the manufacturer sells his product with the LAN board installed? I am very interested in your comments. Best Regards, Pryor McGinnis c...@prodigy.net mailto:c...@prodigy.net www.ctl-lab.com http://www.ctl-lab.com --- This message is from the IEEE EMC
RE: Conducted Emissions on Telecom Ports
Seems more likely I was. Actually, I have run these tests anyway for other reasons I just git riled up by a single segment of the community that imposes restrictions on the rest of the world. Okay, I just get riled up about a lot of stuff. Gary -Original Message- From: Pryor McGinnis [mailto:c...@prodigy.net] Sent: Tuesday, September 05, 2000 8:37 AM To: Gary McInturff; Pettit, Ghery; david_ster...@ademco.com; emc-p...@ieee.org Subject: Re: Conducted Emissions on Telecom Ports Reference CISPR 22:1997, Clause 3.5 telecommunication ports Ports which are intended to be connected to telecommunication networks (e.g. public switched telecommunication networks, integrated services digital networks), local area networks (e.g. Ethernet, Token Ring) and similar networks. This definition indicates that LAN boards such as Ethernet Token Ring will be treated as telecommunication ports and will require conducted emissions to be performed as part of the emission testing. This definition is carried over to EN 55022 and is effective next year. Am I misinterpreting something here? Thanks Pryor - Original Message - From: Gary McInturff gary.mcintu...@worldwidepackets.com To: 'Pryor McGinnis' c...@prodigy.net; Pettit, Ghery ghery.pet...@intel.com; david_ster...@ademco.com; emc-p...@ieee.org Sent: Tuesday, September 05, 2000 10:54 AM Subject: RE: Conducted Emissions on Telecom Ports Define telecom port. A LAN port isn't neccessarily a LAN port. Ethernet ports do not connect directly to the Telecommunications network - a necessary condition before being a telecommunications port. LANS and MANS operate all of the time without any use of any telecommunications equipment. Generally, Ethernet or Fast Ethernet for short distances and Gig Ethernet for longer distances. IF -- the telecommunications lines are needed there is some sort of bridge that takes the ethernet and its digitized Voice over Internet Protocol (Voip) and does all of the phone stuff and makes the actual metallic connection. That birdge has the only telecommunication ports on it. Gary -Original Message- From: Pryor McGinnis [mailto:c...@prodigy.net] Sent: Thursday, August 31, 2000 6:24 AM To: Pettit, Ghery; david_ster...@ademco.com; emc-p...@ieee.org Subject: Re: Conducted Emissions on Telecom Ports Confusing isn't? - Original Message - From: Pettit, Ghery ghery.pet...@intel.com To: david_ster...@ademco.com; emc-p...@ieee.org; c...@prodigy.net Sent: Wednesday, August 30, 2000 5:40 PM Subject: RE: Conducted Emissions on Telecom Ports Actually, it's August 1, 2001 as posted in the OJ on January 25th of this year. You've got 1 less month to start testing to the new standard. Ghery Pettit Intel -Original Message- From: david_ster...@ademco.com [mailto:david_ster...@ademco.com] Sent: Wednesday, August 30, 2000 2:04 PM To: emc-p...@ieee.org; c...@prodigy.net Subject: RE: Conducted Emissions on Telecom Ports The date of withdrawal of EN 55022:1998 is September 1, 2001. Look at the NIC manual's DofC --- the mfgr. may not be declaring compliance to conducted emissions yet. __ Reply Separator _ Subject: Re: Conducted Emissions on Telecom Ports Author: Pryor McGinnis SMTP:c...@prodigy.net at ADEMCONET Date:8/30/2000 10:31 AM Hello All, The question originated from a manufacturer of LAN boards who sells to end users and to manufacturer's who integrate the LAN boards into end products. I advised the LAN board manufacturer that conducted emissions would be required (with boards installed in typical host) on all LAN boards sold to end users and manufacturers of products that integrated LAN boards should test the ports for conducted emission in their end product. The LAN board manufacturer questioned double testing of the LAN boards. His concern is that boards that pass CE in a typical host may not pass in another manufacturer's end product (rub of the green). The LAN Board manufacturer ask for second opinions. Many thanks for your answers. Best Regards, Pryor -Original Message- From: Pryor McGinnis [SMTP:c...@prodigy.net] Sent: Tuesday, August 29, 2000 12:35 PM To: emc-pstc Subject: Conducted Emissions on Telecom Ports Below is a message from a non emc-pstc member. If a manufacturer purchases LAN boards which have been tested for conducted emissions in a host, is the manufacturer required to retest the LAN Ports for conducted emissions if the manufacturer sells his product with the LAN board installed? I am very interested in your comments. Best Regards, Pryor McGinnis c...@prodigy.net mailto:c...@prodigy.net www.ctl-lab.com http://www.ctl-lab.com --- This message is from
Re: Conducted Emissions on Telecom Ports
Reference CISPR 22:1997, Clause 3.5 telecommunication ports Ports which are intended to be connected to telecommunication networks (e.g. public switched telecommunication networks, integrated services digital networks), local area networks (e.g. Ethernet, Token Ring) and similar networks. This definition indicates that LAN boards such as Ethernet Token Ring will be treated as telecommunication ports and will require conducted emissions to be performed as part of the emission testing. This definition is carried over to EN 55022 and is effective next year. Am I misinterpreting something here? Thanks Pryor - Original Message - From: Gary McInturff gary.mcintu...@worldwidepackets.com To: 'Pryor McGinnis' c...@prodigy.net; Pettit, Ghery ghery.pet...@intel.com; david_ster...@ademco.com; emc-p...@ieee.org Sent: Tuesday, September 05, 2000 10:54 AM Subject: RE: Conducted Emissions on Telecom Ports Define telecom port. A LAN port isn't neccessarily a LAN port. Ethernet ports do not connect directly to the Telecommunications network - a necessary condition before being a telecommunications port. LANS and MANS operate all of the time without any use of any telecommunications equipment. Generally, Ethernet or Fast Ethernet for short distances and Gig Ethernet for longer distances. IF -- the telecommunications lines are needed there is some sort of bridge that takes the ethernet and its digitized Voice over Internet Protocol (Voip) and does all of the phone stuff and makes the actual metallic connection. That birdge has the only telecommunication ports on it. Gary -Original Message- From: Pryor McGinnis [mailto:c...@prodigy.net] Sent: Thursday, August 31, 2000 6:24 AM To: Pettit, Ghery; david_ster...@ademco.com; emc-p...@ieee.org Subject: Re: Conducted Emissions on Telecom Ports Confusing isn't? - Original Message - From: Pettit, Ghery ghery.pet...@intel.com To: david_ster...@ademco.com; emc-p...@ieee.org; c...@prodigy.net Sent: Wednesday, August 30, 2000 5:40 PM Subject: RE: Conducted Emissions on Telecom Ports Actually, it's August 1, 2001 as posted in the OJ on January 25th of this year. You've got 1 less month to start testing to the new standard. Ghery Pettit Intel -Original Message- From: david_ster...@ademco.com [mailto:david_ster...@ademco.com] Sent: Wednesday, August 30, 2000 2:04 PM To: emc-p...@ieee.org; c...@prodigy.net Subject: RE: Conducted Emissions on Telecom Ports The date of withdrawal of EN 55022:1998 is September 1, 2001. Look at the NIC manual's DofC --- the mfgr. may not be declaring compliance to conducted emissions yet. __ Reply Separator _ Subject: Re: Conducted Emissions on Telecom Ports Author: Pryor McGinnis SMTP:c...@prodigy.net at ADEMCONET Date:8/30/2000 10:31 AM Hello All, The question originated from a manufacturer of LAN boards who sells to end users and to manufacturer's who integrate the LAN boards into end products. I advised the LAN board manufacturer that conducted emissions would be required (with boards installed in typical host) on all LAN boards sold to end users and manufacturers of products that integrated LAN boards should test the ports for conducted emission in their end product. The LAN board manufacturer questioned double testing of the LAN boards. His concern is that boards that pass CE in a typical host may not pass in another manufacturer's end product (rub of the green). The LAN Board manufacturer ask for second opinions. Many thanks for your answers. Best Regards, Pryor -Original Message- From: Pryor McGinnis [SMTP:c...@prodigy.net] Sent: Tuesday, August 29, 2000 12:35 PM To: emc-pstc Subject: Conducted Emissions on Telecom Ports Below is a message from a non emc-pstc member. If a manufacturer purchases LAN boards which have been tested for conducted emissions in a host, is the manufacturer required to retest the LAN Ports for conducted emissions if the manufacturer sells his product with the LAN board installed? I am very interested in your comments. Best Regards, Pryor McGinnis c...@prodigy.net mailto:c...@prodigy.net www.ctl-lab.com http://www.ctl-lab.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
RE: Conducted Emissions on Telecom Ports
Define telecom port. A LAN port isn't neccessarily a LAN port. Ethernet ports do not connect directly to the Telecommunications network - a necessary condition before being a telecommunications port. LANS and MANS operate all of the time without any use of any telecommunications equipment. Generally, Ethernet or Fast Ethernet for short distances and Gig Ethernet for longer distances. IF -- the telecommunications lines are needed there is some sort of bridge that takes the ethernet and its digitized Voice over Internet Protocol (Voip) and does all of the phone stuff and makes the actual metallic connection. That birdge has the only telecommunication ports on it. Gary -Original Message- From: Pryor McGinnis [mailto:c...@prodigy.net] Sent: Thursday, August 31, 2000 6:24 AM To: Pettit, Ghery; david_ster...@ademco.com; emc-p...@ieee.org Subject: Re: Conducted Emissions on Telecom Ports Confusing isn't? - Original Message - From: Pettit, Ghery ghery.pet...@intel.com To: david_ster...@ademco.com; emc-p...@ieee.org; c...@prodigy.net Sent: Wednesday, August 30, 2000 5:40 PM Subject: RE: Conducted Emissions on Telecom Ports Actually, it's August 1, 2001 as posted in the OJ on January 25th of this year. You've got 1 less month to start testing to the new standard. Ghery Pettit Intel -Original Message- From: david_ster...@ademco.com [mailto:david_ster...@ademco.com] Sent: Wednesday, August 30, 2000 2:04 PM To: emc-p...@ieee.org; c...@prodigy.net Subject: RE: Conducted Emissions on Telecom Ports The date of withdrawal of EN 55022:1998 is September 1, 2001. Look at the NIC manual's DofC --- the mfgr. may not be declaring compliance to conducted emissions yet. __ Reply Separator _ Subject: Re: Conducted Emissions on Telecom Ports Author: Pryor McGinnis SMTP:c...@prodigy.net at ADEMCONET Date:8/30/2000 10:31 AM Hello All, The question originated from a manufacturer of LAN boards who sells to end users and to manufacturer's who integrate the LAN boards into end products. I advised the LAN board manufacturer that conducted emissions would be required (with boards installed in typical host) on all LAN boards sold to end users and manufacturers of products that integrated LAN boards should test the ports for conducted emission in their end product. The LAN board manufacturer questioned double testing of the LAN boards. His concern is that boards that pass CE in a typical host may not pass in another manufacturer's end product (rub of the green). The LAN Board manufacturer ask for second opinions. Many thanks for your answers. Best Regards, Pryor -Original Message- From: Pryor McGinnis [SMTP:c...@prodigy.net] Sent: Tuesday, August 29, 2000 12:35 PM To: emc-pstc Subject: Conducted Emissions on Telecom Ports Below is a message from a non emc-pstc member. If a manufacturer purchases LAN boards which have been tested for conducted emissions in a host, is the manufacturer required to retest the LAN Ports for conducted emissions if the manufacturer sells his product with the LAN board installed? I am very interested in your comments. Best Regards, Pryor McGinnis c...@prodigy.net mailto:c...@prodigy.net www.ctl-lab.com http://www.ctl-lab.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: doubt on conducted emissions
I attach my responses at the end of Mr. Lacey's, in CAPS. I disagree with Mr. Lacey on some details. -- From: Scott Lacey sco...@world.std.com To: Muriel Bittencourt de Liz mur...@grucad.ufsc.br Cc: emc-p...@ieee.org Subject: RE: doubt on conducted emissions Date: Thu, Aug 3, 2000, 6:49 PM Muriel, See answers below. Scott Lacey -Original Message- From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf Of Muriel Bittencourt de Liz Sent: Thursday, August 03, 2000 5:46 PM To: Lista de EMC da IEEE Subject: doubt on conducted emissions Hello Group, I have some doubts concerning conducted emissions: 1. I'll make a hypothetical case: Let's say I have 2 electronic equipment (they can be switched mode power supplies). Equipment A requires 100W. Equipment B requires 3W. Let's say that my readings of conducted emissions, collected in a receiver, are: [EMI of equipment A at f=200kHz]=90 dBuV [EMI of equipment B at f=200kHz]=90 dBuV Making some calculations, I evaluate the interference voltage relative to 90dBuV == EMI in volts= 31.6mV Here begin my questions: # This 31.6mV is a voltage that propagates on the mains wires. I understand that the purpose of the EMC regulations (in the frequency range of 150kHz-30MHz) is to prevent that this voltage interfere with a radio receiver equipment or other electronic equipment. How long this voltage propagates in the mains wires (until which distance it is significant)?? A: Anything on the same branch circuit might be affected. The wire may also act as an antenna and radiate the interference. It may also couple to other circuits that run near it. ANSWER FROM KJJ: IT IS HIGHLY UNLIKELY THAT ANYTHING OTHER THAN A TUNED RADIO RECEIVER COULD BE SUSCEPTIBLE TO 31.6 mV SUPERIMPOSED ON OVER 200 VAC. I SAY 200 VAC, BECAUSE IN THE USA WHERE WE HAVE 120 VAC POWER, WE HAVE NO CE LIMITS BELOW 450 kHz SINCE WE DO NOT HAVE LW RADIO BROADCAST SERVICE. I SAY THAT YOU WOULD HAVE TO INTENTIONALLY DESIGN EQUIPMENT TO SENSE 31.6 mV SUPERIMPOSED ON THE AC LINE. I WOULD NOT WORRY ABOUT COUPLING EITHER, AT 200 kHz, COUPLING IS INEFFICIENT, AND ANYTHING SENSOTIVE TO MILLIVOLT POTENTIALS SHOULD BE SHIELDED ANYWAY. # Is there any difference between the 90dBuV that equipment A (100W) generates to the 90dBuV that equipment B (3W) generates (Qualitative and quantitative)?? A: No. Both are 90 dB relative to 1 uV. The interference, in this case 200 kHz, is mostly a result of circuit layout inefficiencies. The voltage rise time (dv/dt) of the switching element is what generates the interference. Regardless of power ratings, most switch-mode supplies operate at a nominal primary voltage of either 150Vdc (110-120Vac in), or 300Vdc (230-240Vac in or 110-120Vac doubler). KJJ: AGREE. # This 31.6mV has a perturbing effect to the equipment A?? And to equipment B?? A: This interference may have a perturbing effect to any equipment that is sensitive at that frequency or one of its harmonics. KJJ: AS ABOVE, 31.6 mV ONLY AFFECTS A TUNED RADIO RECEIVER. ANY OTHER NON-ANTENNA CONNECTED ELECTRONICS WOULD BE TOTALLY IMMUNE TO SUCH A DISTURBANCE. # Concluding: This voltage is perturbing only for radio receivers?? Is this the goal of the regulations imposed by the agencies (CISPR, FCC, etc.)??? A: This voltage may also affect sensitive analog instruments (causes shifts of reading), may cause false clocking of digital circuits, and so forth. The agencies attempt to address this issue in two ways. First, they set limits for conducted and radiated emissions. Second, they (EC, etc.) require RF immunity testing so that a piece of equipment will not be adversely affected. KJJ: IF A POWER SUPPLY PROVIDED ONLY 40 dB OF ISOLATION AT 200 kHz (note that it provides 80 dB or better at the power frequency) THEN YOU WOULD HAVE 316 uV ON THE Vcc INPUT TO ICs. THE ICs THEMSELVES PROVIDE REJECTION OF NOISE AT Vcc INPUTS. THERE WILL BE NO PROBLEM FOR SENSITIVE ANALOG INSTRUMENTS, AND ESPECIALLY NO PROBLEM FOR DIGITAL CIRCUITS. IN THE USA, THERE EXISTS A REPORT FROM THE NOW DEFUNCT COMPUTER AND BUSINESS EQUIPMENT MANUFACTURERS ASSOCIATION EMC GROUP WHICH EXPLAINS HOW THE CE/RE LIMITS WERE DERIVED (BY CBEMA). THERE IS NO MENTION OF ANY OTHER VICTIM BESIDES BROADCAST RECEIVERS, RADIO AND TV. Thanks in advance for the answers KJJ: YOU ARE WELCOME. Regards Muriel Bittencourt de Liz Group for Conception and Analysis of Electromagnetic Devices GRUCAD/EEL/UFSC Florianópolis, SC Brazil --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy
