Re: SI Unit for volume
Bob: When you go for SI then please stay with the convention, i.e. kilowatt is abbreviated as kW and not KW. We are hopefully beyond the time when MAmp was supposed to mean milliampere. Regards, Bogdan. Robert Wilson wrote: Sorry, you're right. I had meant mW/cc, not W/cc. Until recently Ferroxcube and others had listed their ferrite's hysteresis losses (as a function of frequency and flux density) in terms of mW/cc. Then suddenly their new datasheets changed to KW/m^3. My first reaction was that they must be crazy to apply these enormous units to a ferrite core, a dozen of which would fit in the palm of one's hand! But it quickly became obvious that these units were actually the same as the old mW/cc. Bob Wilson TIR Systems Ltd. Vancouver. -Original Message- From: TM66 [mailto:t...@rcn.com] Sent: June 21, 2002 11:12 AM To: Robert Wilson Subject: Re: SI Unit for volume Bob, W/cc is multiple of KW/m^3. 1 KW = 1,000 W and 1 m^3 = 1,000,000 cc therefore: 1 KW/m^3 = 1,000 W/1,000,000 cc = 0.001 W/cc or 1 W/cc = 1,000 KW/m^3 Robert Wilson wrote: ... For example, in the latest Ferroxcube ferrite core catalogue, specific values of core hysteresis losses are given in KW per m^3 of ferrite material, even though these are the same units as W/cc. ... Regards, Mirko Matejic --- 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 All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- 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 All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Re: An ESD question
Vic: The ambient relative humidity should have no impact on the performance of the gut but only on the generation of static charges. So, to improve the performance in the field, I would suggest that you increase the R.H. at the customer site(s) to about 50% which would eliminate the generation of electrostatic charges and consequently the problems. This will give you time to work on the equipment to minimize ESD susceptibility. By the way, lower R.H. also occurs at low tamperatures. Please let me know how things work out. Bogdan. Gibling, Vic wrote: Dear Group I tried to find David Pommerenke article's in the Journal of ESD on the Web but alas no downloadable version was found, so may I ask the group a question? We have an ESD field failure which is occurring in dry hot countries ( no surprise )which can be recreated with an ESD of -800V. In an attempt to get a high incidence of discharges we used a dehumidifier to create a dry environment. The result was a reduction in discharges. Thinking the problem through -now- as a dry atmosphere will encourage the production of high level ESD and a humid environment inhibits the charge to a lesser level, presumably because it 'leaks' away. Then is it wrong for us to attempt to 'dry' the local atmosphere in the hope of gaining consistent ESD from an ESD gun, that is to say the more humid the environment the more efficiently the discharge will transfer to the victim? Incidentally, to add to the thread regarding intermediate level testing for ESD and EFT. This exercise has revealed different failure mechanisms at different ESD levels. Your views would be appreciated. Vic Gibling Compliance Engineer Marconi Applied Technologies --- 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 All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- 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 All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
(no subject)
My apologies! In the last message I put a wrong address: maHordomo.. and of course the message got rejected - there just ain't no AI in my address book! Gabi: You will have read some more on the subject, so best of good luck to you! Bogdan. bogdan matoga wrote: Gabi: I believe that there is a basic rule which is not published anywhere: when you design something, then do it right. When transient suppressors are needed, then use the correct component, which will not depend on Paschen's Law and give predictable performance. Same for necked down fuses. When you want performance, then do it right. The above original suggestions are perfect for Mickey-Mouse-engineering. Bogdan. --- 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...@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://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Re: 2 Phases in North America
Ken: I think that you did not miss too much - my Physics 101 however was over 50 years ago and harmonics were only mentioned in acoustics! Now, who wins? Greetings, Bogdan. Ken Javor wrote: I haven't been following this train but my recollection of definitions from Physics 101 more than a quarter century ago is that the fundamental is the first harmonic. The first overtone is the second harmonic. These are/were accepted definitions. -- From: Cortland Richmond 72146@compuserve.com To: bogdan matoga bogda...@pacbell.net, ieee pstc list emc-p...@ieee.org Subject: Re: 2 Phases in North America Date: Mon, Dec 17, 2001, 12:04 AM If we're smart (are we?) we'll say fundamental, and let whoever wants to argue what 2nd means have the arena all to themselves! I would say there are harmonics of the second order, third order, and so on, to which we refer, in short, as the second and third harmonics (and so on). Don't forget, though, where the terms came from; what IS harmonic motion, hmm? Cortland --- 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. --- 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: 2 Phases in North America
Gentlemen: I certainly did not intend to start philosophical contortions! Season's greetings and a harmonic(*) New Year! Bogdan. (*) Now what will this start lfresea...@aol.com wrote: Mike, I don't go with you on this one... 0 implies nothing ( prehaps 0 ac ) ... therefore the 0th harmonic is dc??? if a squarewave is made up of odd harmonics, we would have to rethink that, correct? Derek. --- 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: 2 Phases in North America
Cortland: I always thought that 50 Hz or respectively 60 Hz was the 0-th harmonic! Was I mistaken? (I would not be surprised!) (: -) !! Bogdan. Cortland Richmond wrote: This is rather similar to asking what the first harmonic of the power line frequency is. (grin!) Cortland Jayasinghe, Ryan wrote: 180° out of phase? --- 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: 2 Phases in North America
Dear Esquire: May I suggest that you partake in a course called Basic Electricity 001? Bogdan. Cortland Richmond wrote: By the definition below, *single phase* AC would require one wire with no return. I want to see THAT one work before I pay for it! Cortland Richmond (the above being my own opinion, not a statement of my employer's) Robert Johnson wrote: This has just reopened the old two phase controversy again. Ed has done a good job of describing the systems in detail, but be careful with the terms. Ask an electrical engineer about a 120/240 volt home service and he will call it a two phase system. Two phases 180 degrees out of phase is technically correct. --- 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 Heald davehe...@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 emisions - frequencies lower than 150kHz
When I am not mistaken, then VDE0871 required testing starting at 9 kHz. When EMI requirements hit our shores, two tests were run (by some smart manufacturers) one per VDE0871 with a European Line Filter and another with a cheaper FCC Filter. In one particular equipment, there was a peak at 120 kHz, which required that the VDE filter be used (for export), and the local configuration started testing at 150 kHz, all legit. The problem came up when several units were installed in the US, and the remote control of the lights went crazy (the control used 120 kHz as carrier frequency), until the quantity of units was reduced to the original one unit. Well, the fix was to install VDE filters, and everything was quiet. This exercise was quite expensive and helped me to convince management to test and verify that there were no - or not too much - emissions below 150 kHz, and a decent filter was used in the future when necessary for domestic and export products. Bogdan. John: Why would you want to eat mink? John Woodgate wrote: I read in !emc-pstc that gunter_j_ma...@embraco.com.br wrote (in offe76605a.acd9696b-on83256b04.00537...@embraco.com.br) about 'Conducted emisions - frequencies lower than 150kHz', on Wed, 14 Nov 2001: List Nowadays, we run conducted EMI tests according to EN55014-1 to household appliances. The frequency range is 150kHz up to 30MHz. Is there any standard or project to impose limits to lower frequencies ? There is a general *trend* to extend control of emissions down to 9 kHz and up from 2/2.4 kHz to 9 kHz. But this involves a revision or amendment of the standard, so an adequate transition period will be given. To get an idea of what *might* be added, see CISPR15/EN55015. -- 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: (Assault and) Batteries (On The Planet) ...
Terry, Mike and other readers: Thank you for your very refreshing display of common sense and integrity. After reading reams of law and standards in all variations, I was ready to give up on this community. Everybody was attempting to split over again some already split legalistic hairs, but yours was the first contribution that really went for the core. I was tempted to submit as a motto for all this uproar the undying words of J.R. Ewing (you do remember Dallas, don't you?): Once you give up on integrity, everything else comes easy. Regards, Bogdan. Whitehouse, Terence (Terry) wrote: Mike, You deserve an award*** for your refreshing display of common sense. I suggest that we can all learn from your response. As responsible private individuals and regulatory guardians of our corporate interests, we should all be more willing to volunteer to do what is appropriate to protect everybody and everything around us from the (human), mechanical, electrical and toxic hazards so prevalent in our complex society. Too often, we spend time examining legislation and standards to decide how to define the bare minimum to be compliant with the production and use of the items for which we are responsible. As good citizens, we ought not to wait for legislation to force us to do the right thing. There is lots of information readily available, which, in conjunction with the ever louder voice of social conscience, should be more than sufficient for us to discharge our personal and regulatory responsibilities appropriately. *** Take a step outside to reward yourself with some deep breaths of fresh air - while there is still some around to inhale! (For the group members in the UK, as Del Boy would say - ... you know it makes sense ) Terry Whitehouse Avaya Regulatory Milpitas (408) 577-7714 -Original Message- From: Mike Murphy [mailto:mmur...@alesis.com] Sent: Friday, June 15, 2001 2:14 PM To: 'emc-p...@ieee.org' Subject: Batteries ... Doug, From an environmental, not compliance, standpoint, batteries leech nasty chemicals into the groundwater supply as they age in landfills. Enlightened communities sponsor 'hazardous waste roundups' periodically. So, my suggestion is to keep the dead batteries in a sealed container in the home until they can be handed off to qualified disposal specialists such as at these roundups. This is what I do as a matter of course--it's not difficult at all. For Our Little Planet, Mike Murphy --- 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,
Re: Voltage Breakdown
Gentlemen: Let me add my penny's worth to Rich's information. a. Parallel plates provide a homogenous field only in their center, the field fringes at the edges. (One could configure the plates according to Rogowski form). b. The breakdown voltage is not a linear function, even for spherical electrodes. What applies is Paschen's law, which gives the voltage as a function of distance x atmospheric pressure. Have fun! Regards, Bogdan. Rich Nute wrote: Hi Allen: The voltage breakdown of air is presented in IEC 664. There is no fixed number (i.e., mm/kV) that describes or predicts voltage breakdown of air. The principle factor that affects voltage breakdown is the shape of the electrodes (degree of homogeneousness of the electric field between the two electrodes). The more homogeneous the field, the higher the breakdown voltage, and vice versa. For example, at 2 mm, the breakdown of an inhomogeneous field is about 2.5 kV, while the breakdown of an homogeneous field is almost 8 kv! An homogeneous field is created by two parallel planes. An inhomogeneous field is created by a needle-point and a plane. The second factor that affects voltage breakdown of air is the voltage waveshape. The more impulse-type waveshape, the higher the breakdown voltage; the more sinusoidal-type waveshape, the lower the breakdown voltage. The third factor that affects voltage breakdown of air is the air pressure. The higher the air pressure, the higher the breakdown voltage, and vice-versa (Paschen's Law). There are still other factors such as temperature, but these are minor effects compared to the first three. If you are interested, I can send a Powerpoint 4.0 file of the voltage-distance curves of the homogeneousness effect. It covers the distance range from 0 to 2 mm for both homogeneous and inhomogeneous fields for sinsoidal waveforms. The data is taken from IEC 664. Best regards, Rich --- 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
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RE: Title for ENV 50204?
Friends: Does this title make any sense? Or is it that I just don't see it? Bogdan. -Original Message- From: Bailin Ma [SMTP:b...@namg.us.anritsu.com] Sent: Tuesday, July 21, 1998 10:25 AM To: emc-p...@ieee.org; miksher...@aol.com Subject:re: Title for ENV 50204? Radiated Electromagnetic Field from Digital Radio Telephones - Immunity Test - Original Text From: miksher...@aol.com, on 7/21/98 7:11 AM: Quick question: what's the title/subject matter of ENV 50204? thanks! Mike Sherman FSI International miksher...@aol.com or msher...@fsi-intl.com
RE: Ce versus FCC
Sorry, George, I beg to differ and to offer my two bits: 47CFR (Oct. 1, 1997) Para. 15.5 (b) states: Operation of an intentional, unintentional, or incidental radiator is subject to the conditions that no harmful interference is caused and that INTERFERENCE MUST BE ACCEPTED that may be caused by the operation of an authorized radio station, by another intentional or unintentional radiator, by industrial, scientific and medical (ISM) equipment, or by an incidental radiator. Yes, it does not call out ESD interference but neglecting to improve ESD-immunity of your equipment will at least result in nasty letters from customers. I think we should stop splitting legalistic hairs when reality has long ago surpassed the letter of regulations. Finally, 47CFR Para. 15 accepts results per CISPR22, but you can not pick and choose - once you test radiated emissions per CISPR, then you have to use CISPR for conducted emissions as well. Bogdan M. Matoga bogdan.mat...@fibre.com -Original Message- From: geor...@lexmark.com [SMTP:geor...@lexmark.com] Sent: Thursday, July 02, 1998 10:34 AM To: emc-p...@majordomo.ieee.org Subject:Ce versus FCC There are no immunity requirements for FCC, ESD or otherwise. The FCC radiated and conducted EMI limits differ a bit from the European CISPR 22 based limits, but I believe the FCC now accepts either limits. The EMC Directive specifies no particular standard, but one should either use the harmonized standards for EMI and EMS, or will need to use a Technical Construction File to show that no intereference will result. George Alspaugh Lexmark International -- Forwarded by George Alspaugh/Lex/Lexmark on 07/02/98 01:31 PM --- Brian Harlowe bharlowe%vgscientific@interlock.lexmark.com on 07/02/98 12:49:41 PM Please respond to Brian Harlowe bharlowe%vgscientific@interlock.lexmark.com To: emc-pstc%ieee@interlock.lexmark.com cc:(bcc: George Alspaugh/Lex/Lexmark) bcc: George Alspaugh/Lex/Lexmark Subject: Ce versus FCC Can someone out there tell a poor Englishman the basic differences between the requirements of the FCC rules and the requirements to comply with the EEC emc directive. i.e. Do you have to do immunity testing and ESD tests to comply with the FCC rules that sort of thing. Brian Harlowe * opinions expressed here are personal and in no way reflect the position of VG Scientific
RE: EMC/Safety in Poland
George: I am sorry, but your statement that Polish outlets are not always wired correctly is incomplete at best. The problem is the plug, which can be reversed, even when everything is wired correctly. The same problem exists also in Germany. France avoided the possibility of reversal but different configuration of the grounding pin which protrudes from the face of their outlet, the corresponding plug has a female connector for this pin. As far as miswiring of outlets is concerned, you can find that even in the U.S.A., intended to say that even non-reversible plugs are no guarantee that a single pole switch (or fuse) does the job. Furthermore, as far as on/off switches are cincerned, IEC950, Sec. 2.6.2 permits the use of the plug on the power supply cord etc. as a disconnect device. Regards, Bogdan. bogdan.mat...@fibre.com -Original Message- From: geor...@lexmark.com [SMTP:geor...@lexmark.com] Sent: Wednesday, June 17, 1998 12:39 PM To: emc-p...@majordomo.ieee.org Subject:Re: EMC/Safety in Poland Susan, You may find one or more of the following requirments as well: Signed and sealed statements pertaining to your ground continuity and hi-pot testing. Manual statement that the product must be unplugged to reduce power (watts) to zero. Polish law requires all unused ITE to be turned off at night. Some low end ITE do not have on/off switches as at rest power is only 3-5W. Manual statement if the on/off switch does not break both sides (phase and neutral) on line. Polish outlets are not always wired as intended. An inspection of your factory by PCBC inspector. Ours took two days, at our expense. etc.. George Alspaugh Please respond to krzysiak%polbox@interlock.lexmark.com To: emc-pstc%ieee@interlock.lexmark.com cc: Susan Beard sbeard%iu@interlock.lexmark.com (bcc: George Alspaugh) bcc: George Alspaugh Subject: Re: EMC/Safety in Poland Dear Susan, Before obtaining B safety certificate of ITE in Poland you have to deliver: Application form CB Test Certificate CB Test Report Operation manual Service manual Test reports (RFI) to Polish Centre for Testing and Certification (see: http://www.cbscheme.org/country/cbpoland.htm for details) If you don't have any test reports you may let an accredited laboratory in Poland (like this one below) to carry out these tests for you: - safety acc. to PN-93/T-42107 (idt. IEC 950: 1991 +A1: 1992 + A2: 1993), - radiofrequency disturbance acc. to PN-EN 55022: 1996 (idt. CISPR 22: 1993 document). Best regards, Krzysztof Sieczkarek Laboratory of Automatic Identification Techniques Institute of Logistics and Warehousing Poznan, Poland fax +48 61 8526376 http://www.ilim.poznan.pl/la/index_E.html Susan Beard wrote: I recently read an article in Conformity discussing Poland's B mark for safety certification. Could anyone in this group provide more information on both the EMC and safety requirements for shipping ITE into Poland? Thanks in advance. Susan Beard sbe...@xlcomputing.com Cycomm Secure Solutions (formerly XL Computing, Inc.) RCIC - http://www.rcic.com Regulatory Compliance Information Center
RE: interceptor voltage stabilizer
Gentlemen: In the olden times there were also voltage stabilizers based on vacuum tube technology and glow-discharge currents, if I remember correctly. I haven't seen those in a long time, but perhaps they would fill the bill if still available. Bogdan. (7007) 792-6116 bogdan.mat...@fibre.com -Original Message- From: Chris Dupres [SMTP:chris_dup...@compuserve.com] Sent: Tuesday, June 02, 1998 02:45 PM To: Peter Gifford Cc: emc-pstc Subject:Re: interceptor voltage stabilizer Peter, David, Brian et al, et al. Peter, you wrote: Could anyone provide a description to the list of what the voltage stabilizer is supposed to do and how it is accomplished? Possibly a contraption can be made from electronic components. The 'Voltage stabiliser', as it is known , is a very simple, but remarkable ingenious device. It is simply a bimetalic self heating device which has a switch contact operated by the bimetalic element. The contacts are normally closed, and the current flowing to the instruments causes it to heat up and it eventually opens. If the volts are low, the current is lower (Ohms Law - remember?) and the contacts remain closed for longer. Conversely if the volts are high the current will be higher (still Ohms Law) and the contacts will be open for shorter times. Thus the power/voltage applied to the instruments is kept fairly constant. The effect of the slow switching (about every 10 secs or so) doesn't have any effect on the instruments as they are bimetalic too, and have very long thermal time constants. That bit was the simple bit. BUT, because the instruments are indeed bimetalic, they are also affected by ambient temperatures, I mean a half full tank is a half full tank whether in 140 degrees F or in minus 40 (F or C). So the bimetalic regulator automatically allows for the ambient temperature, i.e. takes longer to heat up if it's cold, therby exactly allowing for the bimetalic instrument to also receive the extra bit of voost to keep the reading accurate in cold weather. The converse is, of course, true for hot weather. This works because the bimetalic elements in the instrument and the regulator are virtually identical. Making an electronic version is not trivial, the voltage stability is easy-peasy, but the temperature correction requires look-up-tables, design data, temperature measurement etc. etc. etc. I do electronic stuff for a living and I wouldn't even start. :-) Just a twopence worth of not-so-humble-opinion. Chris Dupres Surrey, UK. 74 JH
Re[3]: Declarations of Conformity and Markings
47 CFR Part 15, para. 107 and 109 identify CISPR 22, 1985 as an alternative to the FCC limits. Inherent is the understanding that once you make the decision to go CISPR then it applies to both radiated and conducted emissions. BTW, I would strongly recommend to check the conducted emissions below 150 kHz, starting at 10 kHz just to be sure that there are no excessive emissions which could interfere with remote control systems. bogdan.mat...@fibre.com __ Reply Separator _ Subject: Re[2]: Declarations of Conformity and Markings Author: Jim Hulberthulbe...@pb.com at Internet List-Post: emc-pstc@listserv.ieee.org Date:2/13/98 4:28 PM I was not aware that Canada had adopted CISPR 22. Can anyone confirm this, as well as answer Dave's question regarding having to meet conducted emissions limits starting at 150 KHz? What about a phase-in period? Thanks in advance. __ Jim HulbertTel:203-924-3621 Senior Engineer - EMC Fax:203-924-3352 Pitney Bowes email: hulbe...@pb.com P.O. Box 3000 35 Waterview Drive Shelton, CT 06484-8000 U.S.A. __ Reply Separator _ Subject: Re: Declarations of Conformity and Markings Author: fryd...@norand.com at SMTPGWY List-Post: emc-pstc@listserv.ieee.org Date:2/13/98 10:43 AM To: All and Benoit Nadeau Several questions are highlighted within the message, most are simple with one underlying point. What are we as EMC and Safety Approval people to do as more and more markings are required? Until a Global approval marking system is adopted, each of us have devised a labeling solution. The development of our individual system reflects the diversity of the our particular equipment we market globally. No one here apparently has responded because it is a difficult predicament. I myself was reluctant to respond, as a minor contributor, hoping someone with more experience would lend some assistance. Matrox has some concerns that we all must deal with. I will keep my responses listed here above the original message. We at Intermec/Norand do not have telecom equipment to approve, we install previously approved modems for each country installation. We do use UHF and spread spectrum transmitters, each of which require licensing and Country approvals. (1) FCC approval via DoC does not require a signature. Just a statement as listed. (2) Canada ICES-003 for us in the USA is not difficult. As long as the product complies to CISPR 22 -1993 the ICES statement can be added. At a recent seminar Brian Kasper of Industry Canada suggested a shortened version of the ICES statement is allowed. Our interpretation follows; Canada: ICES-003, Class (*)*= A or B as appropriate **Question; Since Canada has adopted CISPR 22, must all products meet the conducted emissions requirements from 150 kHz to 30 MHz or does Canada accept conducted emissions to the FCC band, 450 kHZ to 30 MHz? (3) The signatured copy from our perspective must be held by a European representative. The declarations we send with each product do not have the signature but have the statement Signature copy on file. If there is a National Requirement for the signature, I believe by having one available by your EU representative will suffice. (4) New Zealand response from Andrew Dyke andrew.d...@moc.govt.nz New Zealand Regulatory Ministry. Our EMC regime is in a transition mode at present, with the labeling scheme set out in DP10 (C-tick marking) not taking effect until 1 January 1999. Currently the process is, test the product to the appropriate CISPR standard, have the supplier complete a declaration of conformity (there is a form on our website)[use the Austel.com site for links] and send the declaration to me for registering. A declaration fee of NZ$170.65 is payable either by international bank cheque with the declaration, or we can send an invoice. The declaration may be faxed. (5) I have no expertise on Japan requirements. We currently have our products tested and certified by a lab in Japan. Obviously since our products comply to CISPR 22 Class B, Japan has little difficulty accepting them. The MRA with Japan should reduce some of the market roadblocks. (6) Korea has required In Country testing of our products. Hopefully with the Asian Pacific Economic Cooperation MRA that Korea will recognize testing by accredited laboratories. Until the MRA includes Korea, do
Re[4]: Upcoming EMC Seminar
I second Max's presentation. Bogdan. bogdan.mat...@fibre.com __ Reply Separator _ Subject: RE: Re[2]: Upcoming EMC Seminar Author: Max Kelson mkel...@es.com at Internet List-Post: emc-pstc@listserv.ieee.org Date:2/11/98 2:04 PM I would vote to allow a continuation of posting of EMC/safety seminars. This is valuable information and Henry Ott, for instance, is certainly a prestigious contributor to the field. On the flip side, though, I believe that EMC and safety consultants have some obligation to make contributions to this forum and it seems like they never do. In addition, the papers they submit to the journals seem to sometimes lack the detailed information that would make them useful in a practical sense. Even in their seminars some of these experts seem to prefer to simply grind out the same old basic and abstract stuff while saving the more useful information for some special or separate seminar costing still more money. The bottom line, I guess, is that we should start asking them to participate in this forum, when appropriate, in exchange for advertising privileges. I suggest members should also provide negative feedback on seminars that don't provide practical, useful information, substantiated by emissions tests. Max Kelson mkel...@es.com -Original Message- From: Jim Hulbert [SMTP:hulbe...@pb.com] Sent: Wednesday, February 11, 1998 8:56 AM To: emc-p...@ieee.org; richard_c...@iris.scitex.com Subject: Re[2]: Upcoming EMC Seminar According to the Charter and Guidelines (10 March 1995) blatant or overt advertising of goods or services is not permitted. I think this is a good rule. This should not be a forum for free advertising. There are plenty of other appropriate avenues for people to advertise their goods and services. Jim Hulbert __ Reply Separator _ Subject: Re: Upcoming EMC Seminar Author: Richard Cass richard_c...@iris.scitex.com at SMTPGWY Date:2/10/98 8:21 AM I thought that blatant advertising of services, including FOR PROFIT seminars, was not allowed on EMC-PSTC forum. Am I wrong? Regards, Richard Cass __ Reply Separator _ Subject: Upcoming EMC Seminar Author: mlwald...@aol.com at INTERNET Date:2/10/98 4:29 AM We just wanted to take this opportunity to let every one know that there are still a few seats available to attend the EMC Seminar being presented by Mr. Henry Ott and hosted by RhienTexas, Inc. For further information check out the web page at www.rheintech.com/seminar.html. Those of you that wish to attend are urged to register by Febrauary 20, 1998. There is a correction that must be noted about the information provided on the above web page, the price for this two day seminar is not $750 it is $675 per participant. Thank you, Murrell Waldron RhienTexas, Inc. 1701 E Plano Pkwy, Suite 150 Plano, TX 75074 P: 972-509-2566 F: 972-509-0073 email: mlwald...@aol.com
Re: Load Tray Requirements?
Craig: You can not expect to find solutions to all problems that may come up during your work in the standards, you just have to use your head, think the problem through: 1. Are there any sharp edges which could cause injury? 2. Is the force exerted by the closing mechanism high enough to squeeze a finger and is easy withdrawal not possible? 3. Could stalling the motor lead to overheating of the motor and surrounding material? 4. Document the components used and the tests performed and no engineer without legalistic training should be able to fault you, especially if the motor and closing mechanism are defined and periodically inspected to assure that no improvements have been introduced without testing and documentation. Please let me know your solution. Bogdan. bogdan.mat...@fibre.com P.S.: All disclaimers apply. __ Reply Separator _ Subject: Load Tray Requirements? Author: CRAIG HENSLEY hens...@iomega.com at Internet List-Post: emc-pstc@listserv.ieee.org Date:9/16/97 4:58 PM Greetings, I'm looking for any information on safety requirements/guidelines for removable media loading tray mechanisms (i.e., CD-ROM). Specifically what guidelines or requirements should be used to account for the possibility of hair, clothing, fingers, or even a tongue (and who knows what else) from interfering with the operation of the tray mechanism. For example, if I place my finger in the way and then try and close the CD-ROM drive on my computer I feel a small amount of force before the drive tray motor shuts down. There doesn't appear to be enough force to be concerned with. I'm looking for any guidelines, experiences, etc., that should be considered in the design of such a device -- Hopefully from a CD-ROM manufacturer or other manufacturer of products that use a loading tray mechanism. Does evaluation to EN 60950 / UL 1950 take into account this type of potential hazard, or is it more related to Machinery Directive-type standards? Thanks in advance for any information. Craig Hensley Compliance Engineer Iomega Corp. Roy, Utah
Re: Bonding of structures
Rick: I would assume that the main concern is damage to the protective paint layer which gets ripped open and may give access to moisture with potential for corrosion. That is, if you paint the bare steel without any protective coating. If you used zinc plating (or similar) in the first place, no question should arise, although damage to the plating due to the bite of the washers and possible damage to the plating due to slippage of the washer may keep the debate going.. You are right in assuming that the toothed washer provides gas-tight contact (specify a minimum torque requirement before this can gets opened!) but in my opinion, damage to the paint would negate this over time. The way I see it, the question boils down to money (as usual): are you willing to engage in a protracted argument my expert vs. your expert, or would it be cheaper to not paint the areas of concern and provide some selective plating? Another cheap way would be to put some spray paint on the screws after everything has been tightened down, which may lead again to arguments as above. Please let me know how this ends. Bogdan M. Matoga bogdan.mat...@fibre.com __ Reply Separator _ Subject: Bonding of structures Author: Rick Busche rbus...@es.com at Internet List-Post: emc-pstc@listserv.ieee.org Date:6/2/97 16:43 I have a projector assembly which is essentially a large metal structure (frame) with a metal projector platform which swivels for purposes of maintenance. The structure is painted steel, with pressed in bronze bushings at all motion points each of which have been measured at significantly less than 0.10 ohms. Arguably, there is no guarantee that these structures will remain bonded at these levels over time and bonding wires (braid, with crimped ring lugs) have been added across the pivot points. These wires are secured to the structure using a toothed washer and screw. The intent of the toothed washer is to bight through the paint to ensure conductivity. My customer's safety officer (in Europe) is now insisting that the paint must be ground off to bare metal and coated with Zinc paint prior to affixing the lug to the structure. I am concerned that this is an excessive requirement. It has been my understanding that the toothed washer (and the screw for that matter) creates a gas tight connection which is acceptable for all bonding requirements. I would be interested in hearing from the group regarding this bonding issue. I can find no standard or specification which disallows this biting washer or requires Zinc paint. Any comments would be appreciated. Rick Busche rbus...@es.com
