programmable electronic loads; is load noise something to watch f or?
Hello group, we are looking into purchasing a programmable DC electronic load tester for evaluating SMPS. The mainframe unit with one module will provide app. 1200W of loading. Features include constant current and constant resistance modes. Agency claims include CE Class A. How is this type of equipment tested for emissions on the input side? Having never used such a device, I am curious to know if we should be specifying a particular noise figure or parameter in our search. Intuitively, it seems to me there would be some small amount of unwanted noise generated by the excitation of the representative loading components. Wouldn't thermally generated noise be worth considering, or is this negligible? Maybe the output noise of most SMPS swamps out typical electronic load noise? I welcome any recommendations and comments. Chet Summers Pelco email: csumm...@pelco.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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: RADIATED IMMUNITY REQUIREMENTS FOR EN61326
Immunity to broadband transient noise from machines is controlled (e.g., showering arc fast transient requirement). I think that would be more representative of broadband machine noise than a swept cw test such as 61000-4-3. In my opinion, an instantaneous field perhaps much higher than 3 V/m but at some specified low duty cycle repetition rate is much more representative of, and correlatable to, interactions with victim equipment than an amplitude modulated steady state carrier. Therefore I still do not find persuasive the original posting's rationale that 10 V/m should not be relaxed in broadcast bands in industrial areas. on 3/4/03 2:15 PM, John Woodgate at j...@jmwa.demon.co.uk wrote: I read in !emc-pstc that Ken Javor ken.ja...@emccompliance.com wrote (in ba8a53d7.20db%ken.ja...@emccompliance.com) about 'RADIATED IMMUNITY REQUIREMENTS FOR EN61326' on Tue, 4 Mar 2003: I don't understand Mr. Allen's response. If the bands originally cited are reserved for broadcast, then no equipment, including industrial, should intentionally transmit at these frequencies. Further, it is immaterial whether unintentional emissions are controlled to Class A or Class B levels - in either case they are orders of magnitude below 3 V/m. True but high levels of broadband noise many nevertheless occur on a transient time-scale in industrial areas. -- Ken Javor EMC Compliance Huntsville, Alabama 256/650-5261 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: RADIATED IMMUNITY REQUIREMENTS FOR EN61326
I read in !emc-pstc that Ken Javor ken.ja...@emccompliance.com wrote (in ba8a53d7.20db%ken.ja...@emccompliance.com) about 'RADIATED IMMUNITY REQUIREMENTS FOR EN61326' on Tue, 4 Mar 2003: I don't understand Mr. Allen's response. If the bands originally cited are reserved for broadcast, then no equipment, including industrial, should intentionally transmit at these frequencies. Further, it is immaterial whether unintentional emissions are controlled to Class A or Class B levels - in either case they are orders of magnitude below 3 V/m. True but high levels of broadband noise many nevertheless occur on a transient time-scale in industrial areas. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
measurement error
Hi All, This month's Technical Tidbit on http://emcesd.com concerns two sources of errors in scope measurements. The article is linked from the noisy waveform at the bottom of the index page. Abstract: Digitizing oscilloscopes have become one of the most important overall lab instruments over the last ten years. As useful as they are, some interesting problems can occur that affect measurement results. Two such issues are described. Avoiding the problems associated with these issues is straightforward. This article will be of interest especially to the people who troubleshoot immunity problems in our group. Doug -- ___ _ 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. 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
PELV Question
Hello all, In IEC/EN 60204-1 (safety of machinery), one of the conditions required to meet a PELV circuit is: 6.4.1 c) live parts of PELV circuits shall be electrically separated from other live circuits. Electrical separation shall be not less than that required between the primary and secondary circuits of a safety isolating transformer (see IEC 60742). Does anyone know what the required separation between the primary and secondary of a safety isolating transformer? I have a copy of IEC 61558-2-6 which has/will replace IEC 60742 and I was unable to find anything regarding this. Any help you can provide would be greatly appreciated. Sincerely, Nick Momcilovic Product Safety Coordinator QTI mailto:nick.momcilo...@qtiworld.com http://www.qtiworld.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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: RADIATED IMMUNITY REQUIREMENTS FOR EN61326
I don't understand Mr. Allen's response. If the bands originally cited are reserved for broadcast, then no equipment, including industrial, should intentionally transmit at these frequencies. Further, it is immaterial whether unintentional emissions are controlled to Class A or Class B levels - in either case they are orders of magnitude below 3 V/m. on 3/4/03 10:58 AM, John Allen at john.al...@era.co.uk wrote: That's seems quite reasonable because industrial process control equipment is very definitely intended for use within an industrial environment where the worst threats will be local equipment rather than from broadcast services transmitter, because tere is not much point in specifying a reduced-immunity product for use where the local emissions environment is Class A - or worse in the close field - rather than Class B. Regards John Allen -Original Message- From: Provost, Norm [mailto:nprov...@foxboro.com] Sent: 04 March 2003 13:43 To: lisa_cef...@mksinst.com; emc-p...@majordomo.ieee.org Subject: RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 To answer the question regarding relaxation of test levels in EN 61326, there is no relaxation of the rf-immunity test levels for the ITU frequencies (or any frequency) as was the case with the generic standards. Best Regards, Norm Provost -Original Message- From: lisa_cef...@mksinst.com [SMTP:lisa_cef...@mksinst.com] Sent: Tuesday, March 04, 2003 7:53 AM To: emc-p...@majordomo.ieee.org Subject: RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 Has anyone answered the question of whether or not 61326 has provisions for a reduction in the field strength at those frequencies? Lisa Mike Hopkins michael.hopkins@thermTo: 'Ken Javor' ken.ja...@emccompliance.com, Gordon,Ian o.com ian.gor...@edwards.boc.com, 'IEEE EMC-PSTC GROUP' emc-p...@majordomo.ieee.org Sent by: cc: owner-emc-pstc@majordoSubject: RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 mo.ieee.org 03/03/2003 04:07 PM Please respond to Mike Hopkins I believe the other bands are television broadcast M. Hopkins Thermo KeyTek -Original Message- From: Ken Javor [mailto:ken.ja...@emccompliance.com] Sent: Monday, March 03, 2003 11:03 AM To: Gordon,Ian; 'IEEE EMC-PSTC GROUP' Subject: Re: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 Hazarding a guess. I am not near a spectrum usage chart, but clearly 87-108 is the FM broadcast band, and therefore no one else is transmitting at these frequencies, except at very low power. If the other bands listed are also restricted to broadcasters of a certain power, and you can calculate that the closest you might ever approach the source would limit you to a 3 V/m exposure, then the relaxation would make sense. Like I said though, just a guess. on 3/3/03 8:01 AM, Gordon,Ian at ian.gor...@edwards.boc.com wrote: Everybody Can you advise me as to whether the same reduction in field strength is available when applying the industrial immunity requirements of EN61326 as when applying the generic industrial immunity standard EN61000-6-2. EN61000-6-2 permits a reduction in field strength from 10 to 3 V/m over the following frequency ranges : 87 - 108 MHz 174 - 230 MHz 470 - 790 MHz Furthermore, I have never been able to work out why there is a relaxation at these freqs. The wording from table 1 of EN61000-6-2 is 10V/m Except for the ITU broadcast frequency bands (given above) where the level shall be 3V/m. Can anyone provide the logic behind this clause? (I'm sure there is some!). Thanks Ian Gordon _ This e-mail has been scanned for viruses by the WorldCom Internet Managed Scanning Service - powered by MessageLabs. For further information visit http://www.worldcom.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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc -- Ken Javor EMC Compliance Huntsville, Alabama 256/650-5261 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion
Re: Power Factor Correction
I read in !emc-pstc that Dave Spencer dspen...@dsl-only.net wrote (in 185530-22003324161424...@dsl-only.net) about 'Power Factor Correction' on Tue, 4 Mar 2003: I am looking for some input on your experience with PFC as it relates to testing (EN61000-3-2 and EN55022). Has anyone using an AC-AC external transformer in the 15-20 Watt range experienced difficulty passing, e.g. no PFC? Well, you don't say what the transformer is feeding! Assuming it's a bridge rectifier with a fat filter capacitor, the resistances of the transformer windings are usually sufficient to make the rectifier conduction angle exceed 65 degrees, which should be sufficient to meet the Class D limits. BUT those limits doesn't apply below 75 W anyway! One might guess that you haven't read the standard, and have thus been worrying over a non-problem. OTOH, one might, of course, be wrong in an entirely unexpected direction. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: RADIATED IMMUNITY - Some Actual Measurements of FS
I read in !emc-pstc that drcuthbert drcuthb...@micron.com wrote (in cfefa50c9bcad21197470001fa7eba6b14121...@ntexchange05.micron.com) about 'RADIATED IMMUNITY - Some Actual Measurements of FS' on Tue, 4 Mar 2003: Just remember, in words of N6SU if you can't see it it can't hurt you. Doesn't work for gamma rays.(;-) -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
VDE 0100 Part 253, VDE 0298 Part 4
EMC/PSTC'ers, I am researching the ampacity (current-carrying capacity, Leitung in German) of wires for Appendix F of my book, Robust Electronic Design Reference. A WECO catalog pointed me to VDE 0100 Part 253, and searching the Internet I also ran across a number of references to VDE 0298 Part 4 for the ampacity of wires and cables under various installation conditions. Some of the web pages that I found seem to mix values from these two standards, which is very confusing because they seem to differ by 10% for the same wire size, temperature rating for the insulation, ambient temperature, and installation condition (in conduit, in equipment, in cable, in free air). I am willing to buy the standards to resolve this question (even though they seem to be available only in German, as paper copies) if I can find out which ones to buy. I think that I am looking for VDE 0100 part 523.6-81 (VDE 0100 Teil 523.6-81) with tables for Gruppe 1, Gruppe 2, and Gruppe 3 and Tables 3 and 4. Techstreet ( http://www.techstreet.com/ ) lists: * VDE 0100dated 01-May-1973. === this one? * VDE 0100 Beiblatt 1 dated 01-Nov-1982.(Supplement 1) * VDE 0100 Beiblatt 2 dated 01-Mar-1983.(Supplement 2) * VDE 0100 Beiblatt 5 dated 01-Nov-1995.(Supplement 5) If VDE standards are like a lot of the EMC standards, supplements only give the information that has changed, so buying the wrong supplement would just be a waste of my time and money. Similarly, I think that I am looking for VDE 0298 part 4: * VDE 0298-100 dated 01-Dec-1992. * VDE 0298-3 dated 01-Aug-1983. * VDE 0298-300 dated 01-Feb-1997. * VDE 0298-4 dated 01-Aug-1995. === this one? I have E-mailed VDE directly, but don't know if/when I will get a reply from them. Thanks! John Barnes KS4GL, PE, NCE, ESDC Eng, SM IEEE dBi Corporation http://www.dbicorporation.com/ (859)253-1178 phone (859)252-6128 fax 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Power Factor Correction
Hi All, I am looking for some input on your experience with PFC as it relates to testing (EN61000-3-2 and EN55022). Has anyone using an AC-AC external transformer in the 15-20 Watt range experienced difficulty passing, e.g. no PFC? Thanks in advance for your input. Regards, Dave Spencer Two Peppers 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326
That's seems quite reasonable because industrial process control equipment is very definitely intended for use within an industrial environment where the worst threats will be local equipment rather than from broadcast services transmitter, because tere is not much point in specifying a reduced-immunity product for use where the local emissions environment is Class A - or worse in the close field - rather than Class B. Regards John Allen From: Provost, Norm [mailto:nprov...@foxboro.com] Sent: 04 March 2003 13:43 To: lisa_cef...@mksinst.com; emc-p...@majordomo.ieee.org Subject: RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 To answer the question regarding relaxation of test levels in EN 61326, there is no relaxation of the rf-immunity test levels for the ITU frequencies (or any frequency) as was the case with the generic standards. Best Regards, Norm Provost -Original Message- From: lisa_cef...@mksinst.com [SMTP:lisa_cef...@mksinst.com] Sent: Tuesday, March 04, 2003 7:53 AM To: emc-p...@majordomo.ieee.org Subject: RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 Has anyone answered the question of whether or not 61326 has provisions for a reduction in the field strength at those frequencies? Lisa Mike Hopkins michael.hopkins@thermTo: 'Ken Javor' ken.ja...@emccompliance.com, Gordon,Ian o.com ian.gor...@edwards.boc.com, 'IEEE EMC-PSTC GROUP' emc-p...@majordomo.ieee.org Sent by: cc: owner-emc-pstc@majordoSubject: RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 mo.ieee.org 03/03/2003 04:07 PM Please respond to Mike Hopkins I believe the other bands are television broadcast M. Hopkins Thermo KeyTek -Original Message- From: Ken Javor [mailto:ken.ja...@emccompliance.com] Sent: Monday, March 03, 2003 11:03 AM To: Gordon,Ian; 'IEEE EMC-PSTC GROUP' Subject: Re: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 Hazarding a guess. I am not near a spectrum usage chart, but clearly 87-108 is the FM broadcast band, and therefore no one else is transmitting at these frequencies, except at very low power. If the other bands listed are also restricted to broadcasters of a certain power, and you can calculate that the closest you might ever approach the source would limit you to a 3 V/m exposure, then the relaxation would make sense. Like I said though, just a guess. on 3/3/03 8:01 AM, Gordon,Ian at ian.gor...@edwards.boc.com wrote: Everybody Can you advise me as to whether the same reduction in field strength is available when applying the industrial immunity requirements of EN61326 as when applying the generic industrial immunity standard EN61000-6-2. EN61000-6-2 permits a reduction in field strength from 10 to 3 V/m over the following frequency ranges : 87 - 108 MHz 174 - 230 MHz 470 - 790 MHz Furthermore, I have never been able to work out why there is a relaxation at these freqs. The wording from table 1 of EN61000-6-2 is 10V/m Except for the ITU broadcast frequency bands (given above) where the level shall be 3V/m. Can anyone provide the logic behind this clause? (I'm sure there is some!). Thanks Ian Gordon _ This e-mail has been scanned for viruses by the WorldCom Internet Managed Scanning Service - powered by MessageLabs. For further information visit http://www.worldcom.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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc -- Ken Javor EMC Compliance Huntsville, Alabama 256/650-5261 --- 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:
RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326
As far as table A.1 of 61326 indicates, there are no reduction bands. (Table A.1 is for equipment intended for use in industrial locations.) Other types of equimpment covered in EN61326 see a field strength reduction across the whole test band. -Jeff From: lisa_cef...@mksinst.com [mailto:lisa_cef...@mksinst.com] Sent: March 4, 2003 7:53 AM To: emc-p...@majordomo.ieee.org Subject: RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 Has anyone answered the question of whether or not 61326 has provisions for a reduction in the field strength at those frequencies? Lisa Mike Hopkins michael.hopkins@thermTo: 'Ken Javor' ken.ja...@emccompliance.com, Gordon,Ian o.com ian.gor...@edwards.boc.com, 'IEEE EMC-PSTC GROUP' emc-p...@majordomo.ieee.org Sent by: cc: owner-emc-pstc@majordoSubject: RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 mo.ieee.org 03/03/2003 04:07 PM Please respond to Mike Hopkins I believe the other bands are television broadcast M. Hopkins Thermo KeyTek From: Ken Javor [mailto:ken.ja...@emccompliance.com] Sent: Monday, March 03, 2003 11:03 AM To: Gordon,Ian; 'IEEE EMC-PSTC GROUP' Subject: Re: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 Hazarding a guess. I am not near a spectrum usage chart, but clearly 87-108 is the FM broadcast band, and therefore no one else is transmitting at these frequencies, except at very low power. If the other bands listed are also restricted to broadcasters of a certain power, and you can calculate that the closest you might ever approach the source would limit you to a 3 V/m exposure, then the relaxation would make sense. Like I said though, just a guess. on 3/3/03 8:01 AM, Gordon,Ian at ian.gor...@edwards.boc.com wrote: Everybody Can you advise me as to whether the same reduction in field strength is available when applying the industrial immunity requirements of EN61326 as when applying the generic industrial immunity standard EN61000-6-2. EN61000-6-2 permits a reduction in field strength from 10 to 3 V/m over the following frequency ranges : 87 - 108 MHz 174 - 230 MHz 470 - 790 MHz Furthermore, I have never been able to work out why there is a relaxation at these freqs. The wording from table 1 of EN61000-6-2 is 10V/m Except for the ITU broadcast frequency bands (given above) where the level shall be 3V/m. Can anyone provide the logic behind this clause? (I'm sure there is some!). Thanks Ian Gordon _ This e-mail has been scanned for viruses by the WorldCom Internet Managed Scanning Service - powered by MessageLabs. For further information visit http://www.worldcom.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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc -- Ken Javor EMC Compliance Huntsville, Alabama 256/650-5261 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc 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: Ron Pickard: emc-p...@hypercom.com Dave Heald:
RE: RADIATED IMMUNITY - Some Actual Measurements of FS
Why not blast the DUT with 10V/m at all frequencies? If it misbehaves in the 3V/m bands then 3V/m could be tried. If you want some high E-field try my house (or another ham's house). I often run fields to the FCC safety limit in my house. When operating 160 meters I can light a 40 watt fluorescent tube by holding it in my hand at the operating position. I believe the peak limit at 1.8 MHz is 500 V/m. The equipment in my house is not affected (well just a little) with the application of a few ferrites and filters. The field in the adjacent neighbors homes is in the tens of volts/m. No complaints yet. Just remember, in words of N6SU if you can't see it it can't hurt you. Dave Cuthbert WX7G Micron Technology 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326
To answer the question regarding relaxation of test levels in EN 61326, there is no relaxation of the rf-immunity test levels for the ITU frequencies (or any frequency) as was the case with the generic standards. Best Regards, Norm Provost -Original Message- From: lisa_cef...@mksinst.com [SMTP:lisa_cef...@mksinst.com] Sent: Tuesday, March 04, 2003 7:53 AM To: emc-p...@majordomo.ieee.org Subject: RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 Has anyone answered the question of whether or not 61326 has provisions for a reduction in the field strength at those frequencies? Lisa Mike Hopkins michael.hopkins@thermTo: 'Ken Javor' ken.ja...@emccompliance.com, Gordon,Ian o.com ian.gor...@edwards.boc.com, 'IEEE EMC-PSTC GROUP' emc-p...@majordomo.ieee.org Sent by: cc: owner-emc-pstc@majordoSubject: RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 mo.ieee.org 03/03/2003 04:07 PM Please respond to Mike Hopkins I believe the other bands are television broadcast M. Hopkins Thermo KeyTek -Original Message- From: Ken Javor [mailto:ken.ja...@emccompliance.com] Sent: Monday, March 03, 2003 11:03 AM To: Gordon,Ian; 'IEEE EMC-PSTC GROUP' Subject: Re: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 Hazarding a guess. I am not near a spectrum usage chart, but clearly 87-108 is the FM broadcast band, and therefore no one else is transmitting at these frequencies, except at very low power. If the other bands listed are also restricted to broadcasters of a certain power, and you can calculate that the closest you might ever approach the source would limit you to a 3 V/m exposure, then the relaxation would make sense. Like I said though, just a guess. on 3/3/03 8:01 AM, Gordon,Ian at ian.gor...@edwards.boc.com wrote: Everybody Can you advise me as to whether the same reduction in field strength is available when applying the industrial immunity requirements of EN61326 as when applying the generic industrial immunity standard EN61000-6-2. EN61000-6-2 permits a reduction in field strength from 10 to 3 V/m over the following frequency ranges : 87 - 108 MHz 174 - 230 MHz 470 - 790 MHz Furthermore, I have never been able to work out why there is a relaxation at these freqs. The wording from table 1 of EN61000-6-2 is 10V/m Except for the ITU broadcast frequency bands (given above) where the level shall be 3V/m. Can anyone provide the logic behind this clause? (I'm sure there is some!). Thanks Ian Gordon _ This e-mail has been scanned for viruses by the WorldCom Internet Managed Scanning Service - powered by MessageLabs. For further information visit http://www.worldcom.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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc -- Ken Javor EMC Compliance Huntsville, Alabama 256/650-5261 --- 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion
RE: RADIATED IMMUNITY - Some Actual Measurements of FS
But, does EN 61326 give a reduction from 10 to 3V/m at certain frequencies. I do not think so, for an industrial location, Annnex A, Table A.1, IEC 61000-4-3 is 10V/m. From: John Woodgate [mailto:j...@jmwa.demon.co.uk] Sent: Tuesday, March 04, 2003 12:58 AM To: emc-p...@majordomo.ieee.org Subject: Re: RADIATED IMMUNITY - Some Actual Measurements of FS I read in !emc-pstc that Jacob Schanker schan...@frontiernet.net wrote (in 006d01c2e1fa$7f0060c0$6401a8c0@net1) about 'RADIATED IMMUNITY - Some Actual Measurements of FS' on Mon, 3 Mar 2003: I hope this lengthy response was enlightening. It's extremely useful confirmation of the basis for the '3 V/m' reduced test level, for which I bear a small part of the responsibility. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326
Has anyone answered the question of whether or not 61326 has provisions for a reduction in the field strength at those frequencies? Lisa Mike Hopkins michael.hopkins@thermTo: 'Ken Javor' ken.ja...@emccompliance.com, Gordon,Ian o.com ian.gor...@edwards.boc.com, 'IEEE EMC-PSTC GROUP' emc-p...@majordomo.ieee.org Sent by: cc: owner-emc-pstc@majordoSubject: RE: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 mo.ieee.org 03/03/2003 04:07 PM Please respond to Mike Hopkins I believe the other bands are television broadcast M. Hopkins Thermo KeyTek From: Ken Javor [mailto:ken.ja...@emccompliance.com] Sent: Monday, March 03, 2003 11:03 AM To: Gordon,Ian; 'IEEE EMC-PSTC GROUP' Subject: Re: RADIATED IMMUNITY REQUIREMENTS FOR EN61326 Hazarding a guess. I am not near a spectrum usage chart, but clearly 87-108 is the FM broadcast band, and therefore no one else is transmitting at these frequencies, except at very low power. If the other bands listed are also restricted to broadcasters of a certain power, and you can calculate that the closest you might ever approach the source would limit you to a 3 V/m exposure, then the relaxation would make sense. Like I said though, just a guess. on 3/3/03 8:01 AM, Gordon,Ian at ian.gor...@edwards.boc.com wrote: Everybody Can you advise me as to whether the same reduction in field strength is available when applying the industrial immunity requirements of EN61326 as when applying the generic industrial immunity standard EN61000-6-2. EN61000-6-2 permits a reduction in field strength from 10 to 3 V/m over the following frequency ranges : 87 - 108 MHz 174 - 230 MHz 470 - 790 MHz Furthermore, I have never been able to work out why there is a relaxation at these freqs. The wording from table 1 of EN61000-6-2 is 10V/m Except for the ITU broadcast frequency bands (given above) where the level shall be 3V/m. Can anyone provide the logic behind this clause? (I'm sure there is some!). Thanks Ian Gordon _ This e-mail has been scanned for viruses by the WorldCom Internet Managed Scanning Service - powered by MessageLabs. For further information visit http://www.worldcom.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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc -- Ken Javor EMC Compliance Huntsville, Alabama 256/650-5261 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
Re: RADIATED IMMUNITY - Some Actual Measurements of FS
I read in !emc-pstc that Jacob Schanker schan...@frontiernet.net wrote (in 006d01c2e1fa$7f0060c0$6401a8c0@net1) about 'RADIATED IMMUNITY - Some Actual Measurements of FS' on Mon, 3 Mar 2003: I hope this lengthy response was enlightening. It's extremely useful confirmation of the basis for the '3 V/m' reduced test level, for which I bear a small part of the responsibility. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: E.S. of plastic xstr case
I read in !emc-pstc that Jim Ericson jde...@nas.com wrote (in 003c01c2e1fb$239b0cc0$b4663fce@pavilion) about 'E.S. of plastic xstr case' on Mon, 3 Mar 2003: Jim Ericson Acme Testing Company Acme, Washington j...@acmetesting.com Do you employ Wyle E Coyote or is he an independent test-house? (;-) Am I the ten millionth person who asked? -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Sweeny Static Voltmeter L127E (tritium source)
We still have an ancient sweeney static meter sitting on the shelf. Does anyone know how to safely dispose of this? I seem to recall a similar posting some years ago but I don't remember the outcome. Regards Mike Hurley Mead Testing Ltd. Unit 25 Mead Industrial Park Riverway Harlow CM20 2SE Phone 01279 635864 Fax 01279 635874 mailto:mikehur...@meadtest.com mikehur...@meadtest.com www.meadtest.com
Re: RADIATED IMMUNITY - Some Actual Measurements of FS
On the issue of broadcast field strengths, I can provide some input based on a TV/FM field strength study I completed last December for a local municipality. The Town of Brighton and the City of Rochester New York are somewhat unique in having the main broadcast tower cluster located on a hill in the middle of a populated residential/commercial area. In most towns in the US, the TV towers are outside of highly populated areas. I know there are other exceptions - no need to point them out to me. The residents have long experienced interference problems with their consumer electronics, garage door openers, and who knows what else because of the high field strength levels in the vicinity of the towers. The Town of Brighton established a task force on the issue, which I participated in as a volunteer, to give some technical moderation to the proceedings. You can find my contribution to that group on the Town's website at www.townofbrighton.org/interference.html. The Town also commissioned me and a colleague to do a formal field strength survey of signals in the area surrounding the towers. The results of interest here are that with 240 individual measurements made (12 stations at 20 locations) there were only two instances of field strength levels exceeding 2 V/m. Both were for a UHF station on channel 31 (573.25 MHz visual carrier frequency). At one location 957 meters from the tower, the signal was 2.483 V/m. At another, 3040 meters from the tower (and clear line of sight) the level was 2.630 V/m. The station runs several megawatts erp. The closest site measured was 221 meters from the towers. There, the channel 31 station measured 741.3 mV/m. However, an FM station at 96.5 MHz measured 1.762 V/m by comparison, and the FM runs at 50 kW erp (possibly 50 kW horizontal and 50 kW vertical polarization).] All measurements were made with Potomac Instruments field strength meters and tunable dipole antennas. Everything was calibrated by the manufacturer. Summing up, it would appear, from this study at least, that the contention that signal levels in excess of 2 V/m at the broadcast frequencies are unlikely to be found is justified. Getting back to the interference problem, there's a lot of consumer electronics that does not like 2 V/m or anything even approaching it. Manufacturers, as you are all aware, don't spend an extra cent if it is not absolutely required or they would not get caught - (many, perhaps not all). The FCC does not have any immunity requirements to speak of. One of the reasons signal levels don't get too excessive near a tower (besides that the antennas are a hundred or several hundred meters up as was already mentioned by someone) is a matter of simple geometry. There is not much downtilt to broadcast antenna vertical radiation patterns. So nearby, the radiation is already well down the dB curve of the main lobe. I spent many midnight hours years ago under the tower of two FM stations (I was Director of Engineering for one of them) and I could operate an oscilloscope and a 1948 RCA FM radio with no problem at all. I hope this lengthy response was enlightening. Regards, Jacob Z. Schanker, P.E. Consulting Engineer 65 Crandon Way Rochester, NY 14618 USA Tel: 585 442 3909 Fax: 585 442 2182 j.schan...@ieee.org 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: E.S. of plastic xstr case
Brian: Transistor and Integrated Circuit plastic encapsulants usually are some recipe of Epoxy Novolac. I'd suggest doing a Google search for [Epoxy Novolac +electrical characteristics]. Or, do an end run on a manufacturer. You might try calling Philips Semiconductor on Arques Avenue in Sunnyvale, California. Ask for Bill Hobdy. He's an epoxy expert there. I worked with him for many years, so use my name if it helps get through the maze. Good luck! Jim Ericson Acme Testing Company Acme, Washington j...@acmetesting.com - Original Message - From: boconn...@t-yuden.com To: emc-p...@majordomo.ieee.org Sent: Monday, March 03, 2003 11:40 AM Subject: E.S. of plastic xstr case Good People of PSTC: I have noted that there is a CCA decision stating that the plastic enclosure of a semiconductor cab be considered as basic insulation... But I cannot find manufacturers' specs listing the dielectric strength of the plastic case (e.g., TO-0220). Am I overlooking an obvious data source? They must design this in, because all of the FETs that I have tested do ok up to approx 2500Vdc. thanks much. R/S, Brian
