Re: A Different Kind of EMC Problem
Don, and the group, This is not so complex. As you surmise, parts of the house wiring are being switched in and out by devices on it, and the broadcast RF present on the wiring is being modulated by that switching. While probing around the house with an untuned RF detector, I've found power and thermostat wiring to be RF hot -- but using a meter with a detector in it (Credence Technology's EM-Eye) I was able to confirm it was RF from several nearby AM radio stations and not generated by devices actually on the line. Several volts of RF may be present on home wiring. The cure is either to remove the RF from the wiring (easier to say than do) OR to isolate the switching devices from the power line at RF - and THAT is feasible. As to whether there are standards that apply to modulation interference, the only one I can think of concerns flicker. The *FAA* has rules on what conducting structures may be built near a VOR (possibly other NAVAIDS, too) because of re-radiation, but I don't think they address errors due to intermittent connections from structures outside the clear zone. As an aside, I've suggested to other QRP enthusiasts that one could operate at *zero* RF power by switching a sufficiently large antenna to modulate another station's signal. One early radio system did use such modulation of the natural electric field for wireless telegraphy over a distance of some miles. 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: 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
IEC60065 and Canadian requirements
Safety folks, Assume testing according to IEC60065, which other tests / requirements will be in addition for Canada (national requirements) ? Best regards Amund Westin, Oslo / Norway
Re: TC77b Rewrite of 61000-4-2 and 61000-4-4
I read in !emc-pstc that John Woodgate j...@jmwa.demon.co.uk wrote (in hzkt6eaugh09e...@jmwa.demon.co.uk) about 'TC77b Rewrite of 61000-4-2 and 61000-4-4' on Wed, 13 Nov 2002: Also, the boilerplate text for Normative References clauses has been changed to: QUOTE The following normative documents contain provisions which, through reference in this text, constitute provisions of [insert reference of standard or section]. At the time of publication, the editions indicated were valid. All normative documents are subject to revision, and parties to agreements based on [insert reference of standard or section] are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. Members of IEC and ISO maintain registers of currently valid international standards. Oops, sorry, that's the OLD text. THIS is the new text: QUOTE The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ENDQUOTE -- 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 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: A Different Kind of EMC Problem
If the problem were emissions, the interference would be very audible with the radio station off the air. Just a rambling thought pattern ... I'm not sure I necessarily agree with this. If the radio carrier drops off, the front end stage and intermediate stages aren't carrying an rf signal through to the demodulation stages. If 60 Hz is indeed getting into the radio to the demodulation stage by way of radiation, it's not doing it through the front end or intermediate stages. Those filter stages wouldn't carry something as low as 60Hz. Therefore, you may very well hear nothing with no station carrier present. 60Hz most definitely will be heard if it's inductively effecting the radio if the station is broadcasting or if it's off. That I agree. And if the induction is sufficiently high, you may well hear the 60Hz through the speaker when the radio is even turned off. This is one of the ways which they used to sweep a room for listening devices. Regards, Doug McKean --- 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: Radiated immunity testing above 1 GHz
They're usually VSWR tripped. I f you want one to operate with high vswr, then you need a circulator or isolator to absorb the reverse power. -- From: richwo...@tycoint.com To: emc-p...@majordomo.ieee.org Subject: Radiated immunity testing above 1 GHz Date: Wed, Nov 13, 2002, 8:00 AM I need to make a decision on an amplifier for radiated immunity testing in the 1-2 GHz range. The choices appear to be a new solid state amplifier ( I have not located a used one) or a used TWT amp. Is anyone using a TWT amplifier for radiated immunity testing above 1 GHz? Do I need to be concerned about protecting the tube from damage caused by excessive VSWR cause by, perhaps, chamber effects? Is there anything else I need to know about TWT amps (yeah, I know - throw it way if the tube dies)? Richard Woods Sensormatic Electronics Tyco International --- 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: GR-78 Circuit pack ESD test.
Strongly suggest you consider using the IEC test from 1089, which is supposed to be the primary environmental document anyway It's based on IEC, simulators are readily available, and it's a realistic test with a lot of precidence Hope this is helpful, Best Regards, Mike Hopkins Thermo KeyTek Michael, I am surprised as well, and would love to do exactly that but it is GR-78 is still being identified and there is a dichotomy in test methods between this reference GR-78 and the GR-1089 reference. GR-1089 discusses ESD on final equipment, and does reference IEC 801 methods. GR-78 calls out circuit pack handling tests and identifies the waveform we are discussing. E.G. The board is removed and several discharges around the periphery of the pack later it is re-installed into the chassis to verify functionality. At least on RBOC requires GR-78 circuit pack tests as part of its equipment checklist and full compliance with the NEBS requirements, as they see it, others may/do not. Unlike government standards like the FCC or EN standards they don't carry the weight of law, they are part of the purchase agreement. That actually makes them worse than public standards because the customer can pick and choose the sections they feel are pertinent and which are not and currently there is no consensus between the customers. The reviewing arms at each of these customers is inundated with work and unless you have a specific project open with them they simply haven't the time to respond to random inquiries. Even if you have a current project customer A might say use the IEC waveforms and company B says follow the standard. Even when weaknesses in the standards are identified and are addressed by technical committees (1089 and 63 both have updates - and 78 has gone from a TR to a GR but with no changes in the ESD waveform) there is no consensus among the parties. In fairness to that group most have participated and agreed to the revised standards, but pretty much a single entity, for reasons that are unfathomable at best, has rejected them and put forth their own version. The remaining RBOC's aren't accepting it, and in my understanding for good reason. Heavy sigh! It really is the definition of, Between a rock and a hard place. I guess Damned if I do and Damned is also applicable. The confusion fuels an ego and costs the industry money but what are you going to do? Thanks Gary --- 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: Laser safety questions
Well, In response to question 1, you may want to try for Class 1M. The new measurement geometries allow many class 3B lasers to be reclassified as 1M. I would assume (although I have no direct experience here) that the visible spectrum lasers would also benefit from the new geometries (BTW, the Class 1M spectrum is 302.5 to 4000nm). Wouldn't it be wonderful to have all Class 1(M) lasers?!! Best Regards, Dave Heald -Original Message- From: Gandler, Mark [mailto:mgand...@ciena.com] Sent: Tuesday, November 12, 2002 1:47 PM To: 'emc-p...@majordomo.ieee.org' Subject: Laser safety questions Hello Group, According to the new revision of IEC 60825-1 (2001-08) , there are following laser products classes: 1, 1M, 2, 2M , 3R , 3B and 4, instead of 1, 2 , 3A, 3B and 4 per previous revision. Question # 1 : should we change the labeling, let's say from 3A to 3R? Is it any timetable for implementation? The latest revision that I have for IEC 60825-2 is 2000-05 and classification there still 1,2,3A ,k 3A, 3B and 4. Question # 2 : is it any newer version of 60825-2 available? and if yes, what are the classes in it? Is it correct to assume that if somebody asking for laser power density , so I need to look for maximum permissible exposure (MPE)? If not , what it could be? If yes, what is the easiest (or only) way to calculate it? Let say the wavelength is 1550 nm, located on PCB , than after 10 mm or so is a connector, exposure is 100s. Any ideas? The MPE in the IEC table is 1000W/m2. Thank you in advance, Mark Gandler Ciena --- 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: E-field probe for immunity testing
In a message dated 11/13/2002 8:07:17 AM Central Standard Time, gui...@cae.com writes: I have an IFI (think it stands for Instruments For Industry) E-field probe, purchased years ago. It still works fine. It comes with various probe tips (antennas) tuned for low/high V/m, and it has its in-built attenuator. It covers 25 to 500MHz and 1 to 100 V/m top of the scale; works on batteries and it has a fiber link to a remote indicator powered from the mains. Alexandru Guidea CAE Inc. I have a couple of these for sale if anyone is interested... The levelling pre-amp too... Cheers, Derek.
RE: E-field probe for immunity testing
I have an IFI (think it stands for Instruments For Industry) E-field probe, purchased years ago. It still works fine. It comes with various probe tips (antennas) tuned for low/high V/m, and it has its in-built attenuator. It covers 25 to 500MHz and 1 to 100 V/m top of the scale; works on batteries and it has a fiber link to a remote indicator powered from the mains. Alexandru Guidea CAE Inc. I am seeking sources for an E-field probe for radiated immunity testing other than Holaday and Amplifier Research. Any suggestions? Richard Woods Sensormatic Electronics Tyco International --- 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
Radiated immunity testing above 1 GHz
I need to make a decision on an amplifier for radiated immunity testing in the 1-2 GHz range. The choices appear to be a new solid state amplifier ( I have not located a used one) or a used TWT amp. Is anyone using a TWT amplifier for radiated immunity testing above 1 GHz? Do I need to be concerned about protecting the tube from damage caused by excessive VSWR cause by, perhaps, chamber effects? Is there anything else I need to know about TWT amps (yeah, I know - throw it way if the tube dies)? Richard Woods Sensormatic Electronics Tyco International --- 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: E-field probe for immunity testing
HI Richard, Running the risk of being commercial here... You know Schaffner maybe coming out with their own probe? Cheers, Derek.
RE: Laser safety questions
Mark, Regarding question #1 Perhaps your question is based on the misconception that in Europe and elsewhere we use IEC standards directly. This in fact is not the case. For Europe we use ENs agreed by CENELEC and published by national standards bodies, such as BSI. These ENs are frequently either based on, or identical to, IEC standards: however they are not IEC publications per se. The same is also true in other parts of the world, such as Australia. The OJEC list of standards offering a presumption of conformity with the LVD provides information that the second amendment to EN 60825-1 does provide a presumption of conformity with the LVD. Moreover, Amendment 2 (which contains the newer classifications) supersedes the earlier amendment (A11 - containing the older classifications) on 1 Jan 2004. Until 1 Jan 2004 you can you use the new or the old classifications, at your choice. Regarding question #2 No there is currently no published version of IEC (or EN) 60825-2 that references the newer Classes in Amendment 2 of 60825-1. IEC TC76, the committee responsible for the IEC 60825-x series of standards is, however, in the process of preparing such an update. In the interim the IEC have available an 'Interpretation Sheet' that explains how you could amend IEC 60825-2 to use the newer class designations. However, there is also disagreement regarding the value of this Interpretation Sheet: more I will not say. Finally, IEC 60825-2 does not contain any 'Class' designations. This standard has 'Hazard Level' designations which take into account the fact that optical networks may utilise high optical powers to transmit data along a contiguous fibre path providing that there is an Automatic Power Reduction feature (of adequate reliability) to decrease the output to a safe value in the event of a fault. Of course, the Hazard Level designations in part 2 refer to the AELs and MPEs for the corresponding Class in part 1. Opinions as always, Richard Hughes. -Original Message- From: Gandler, Mark [mailto:mgand...@ciena.com] Sent: 12 November 2002 18:47 To: 'emc-p...@majordomo.ieee.org' Subject: Laser safety questions Hello Group, According to the new revision of IEC 60825-1 (2001-08) , there are following laser products classes: 1, 1M, 2, 2M , 3R , 3B and 4, instead of 1, 2 , 3A, 3B and 4 per previous revision. Question # 1 : should we change the labeling, let's say from 3A to 3R? Is it any timetable for implementation? The latest revision that I have for IEC 60825-2 is 2000-05 and classification there still 1,2,3A ,k 3A, 3B and 4. Question # 2 : is it any newer version of 60825-2 available? and if yes, what are the classes in it? Is it correct to assume that if somebody asking for laser power density , so I need to look for maximum permissible exposure (MPE)? If not , what it could be? If yes, what is the easiest (or only) way to calculate it? Let say the wavelength is 1550 nm, located on PCB , than after 10 mm or so is a connector, exposure is 100s. Any ideas? The MPE in the IEC table is 1000W/m2. Thank you in advance, Mark Gandler Ciena --- 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: A Different Kind of EMC Problem
I read in !emc-pstc that Ken Javor ken.ja...@emccompliance.com wrote (in 0h5h004i9i0...@mtaout06.icomcast.net) about 'A Different Kind of EMC Problem' on Tue, 12 Nov 2002: I am going to guess that the three devices you list as culprits did not have any requirement to meet a conducted emission limit. See below. Just like an SCR-based light dimmer, they can chop the ac line with impunity. When I used to teach seminars, and do demos in hotels, I learned not to rely on being able to use AM radios in a hotel conference room - the large amounts of fluorescents and other dirty loads, totally uncontrolled by any standards - often made AM reception impossible. [sigsnip] I have three devices in my house that cause problems with AM radio band reception, but not due to emissions, In each case, the device adds modulation to strong AM signals, synchronous with the power line. The three devices are: 1. A stereo adaptor for a Beta VCR, CISPR13/EN55013 applies, and sets limits on conducted disturbances via the mains lead. The product would almost certainly not work with the VCR if its rectifier didn't have capacitors across it to eliminate rectification spikes. 2. A dishwasher with electronic controller, 3. An electric toothbrush charger. CISPR14-1/EN55014-1 applies, and sets limits on conducted disturbances via the mains lead. -- 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 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: E-field probe for immunity testing
Wandel and Goltermann, and Narda both make field probes. I belive the WG probes are fiber optically linked. The older Narda probes aren't and are not suitable. I'm not sure what their latest products look like. Luke Turnbull richwo...@tycoint.com 11/12/02 05:11pm I am seeking sources for an E-field probe for radiated immunity testing other than Holaday and Amplifier Research. Any suggestions? Richard Woods Sensormatic Electronics Tyco International --- 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: E-field probe for immunity testing
Suggestion : Wandel Goltermann Regards, Véronique richwo...@tycoint.com wrote: I am seeking sources for an E-field probe for radiated immunity testing other than Holaday and Amplifier Research. Any suggestions? Richard Woods Sensormatic Electronics Tyco International --- 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 -- Ir. Véronique Beauvois Université de Liège Département d'Electricité, Electronique et Informatique Service d'Electricité Appliquée (Prof. W. Legros) Institut Montefiore B28 4000 LIEGE - BELGIQUE Tél: +32-4-3663746 GSM: 0477/87.12.80 Fax: +32-4-3662910 http://elap.montefiore.ulg.ac.be --- 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: TC77b Rewrite of 61000-4-2 and 61000-4-4
Doug - we posted within a half-hour it seems. ;) Actually the designers I worked-with liked the idea that the chips they bought were tested, at least in some way, against the same standard the end-product faced. I guess I would regard it as better than nothing information. Granted, it can be very misleading to claim a component can meet an EMC standard. However, that is a very useful approach for safety, a whole 'nother topic. I will make one last point. [I hear cheers?] Some designers, especially those that struggled to pass a test you now deem unduely difficult, do not always greet that news (we overtested it) in a positive manner. [Long story on the matter withheld.] Best Regards, Eric Lifsey e.lif...@ieee.org http://ewh.ieee.org/r6/utah/ --- 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: TC77b Rewrite of 61000-4-2 and 61000-4-4
HI Eric and the group, The main difference in the ESD test is in how the waveform is specified. The waveform is not being changed, just a better specification and calibration procedure for the simulator. Some ESD simulators may need little or no change while others will need a redesign. Some changes to testing procedure will make testing easier to pass because the original intent in the test was not explicit enough and resulted in overtesting. In any event a new document is sometime in the future as far as being in place in the EU requirements. Since document changes can still take place, it would not be wise to change any decisions now, even if you had the draft document. But, to keep things in perspective, the price of an ESD simulator a few years from now, when the standard MAY be in place, will be small compared to your cost if a perfectly good product fails because the simulator can pass calibration, yet significantly overstress your equipment compared to a different brand of simulator. I think everyone's cost will in fact be lower overall. There has been a tendency lately for chip manufacturers to claim their chips pass IEC 61000-4-2 in their advertising. This test was never intended for chips and has no methodology to do such a test. The wording in the document will make it plain that it is a misapplication of 61000-4-2 to test chips with it. Another problem resolved. Doug On Tuesday, Nov 12, 2002, at 09:54 US/Pacific, hellflo...@aol.com wrote: I want to make sure everyone is aware of the tidbit of information Doug offered on the GR-78 thread. Readers may want to reconsider capital equipment purchases of related test equipment, and certainly the impact on manufacturers of sustained product lines (typically industrial) over the next three or four years. In a message dated 11/11/02 11:08:35 PM, d...@emcesd.com writes: Interesting coincidence, I am in Chandler, AZ USA for a meeting of IEC TC77b (high frequency immunity) to rewrite the ESD (61000-4-2) and the EFT (-4) specs. The new test will be quite different than the existing one with the main benefit being more repeatable results. Comment - I applaud efforts to improve a test, however the broad impact of these standards may not help the EMC community gain favor with corporate management. Best Regards, Eric Lifsey e.lif...@ieee.org http://ewh.ieee.org/r6/utah/ --- 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 ___ _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 \ _ /]\ _ / Web: 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 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: GR-78 Circuit pack ESD test.
Gary -- I just had the office email me a copy of the simulator description from GR-78 and I'm amazed this is still in use. In the last few years, there has been a lot of new data, and standards for ESD have evolved considerably (BELLCORE GR 1089 is essentially the same as IEC 61000-4-2). Verfiying the waveform using a scope and target with a bandwidth of only 350MHz is less than adaquate -- work being done today uses 3.5GHz scopes and 10GHz targets in order to insure that the high frequency ringing and actual current amplitudes are observed. Anyway, that isn't the point --- we, or others, could provide an ESD gun with virtually any R, and any C up to about 1000pf (bigger caps won't fit into some guns). What I'm not sure of is whether or not we can fit into the waveform specifications: 2 - 10ns is extemely slow -- IEC and Bellcore are all 0.7 to 1ns and ANSI is 400ps, AND to measure the peaks with a 350MHz bandwidth scope would require adding some filtering -- if we use our faster scopes and targets, we'll see the REAL peak current, that will likely be quite a bit higher than the tables of GR78 show. Don't know about the durations, but we these could be measured easily -- they are probably okay because they're not so dependant on the bandwidth of the scope/target combination. Strongly suggest you consider using the IEC test from 1089, which is supposed to be the primary environmental document anyway It's based on IEC, simulators are readily available, and it's a realistic test with a lot of precidence Hope this is helpful, Best Regards, Mike Hopkins Thermo KeyTek - Original Message - From: Gary McInturff gary.mcintu...@worldwidepackets.com To: EMC-PSTC (E-mail) emc-p...@ieee.org Sent: Monday, November 11, 2002 6:43 PM Subject: GR-78 Circuit pack ESD test. Anybody know what equipment provides the waveform described above? Its much slower than the IEC801 waveform. I tried Keytek and they don't have it. Other suggestions to perform the test - just use the IEC waveform? Gary --- 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: A Different Kind of EMC Problem
I read in !emc-pstc that don_borow...@selinc.com wrote (in OF685C23FA.C efd2279-on88256c6f.006f0...@selinc.com) about 'A Different Kind of EMC Problem' on Tue, 12 Nov 2002: I have three devices in my house that cause problems with AM radio band reception, but not due to emissions, In each case, the device adds modulation to strong AM signals, synchronous with the power line. The three devices are: 1. A stereo adaptor for a Beta VCR, 2. A dishwasher with electronic controller, 3. An electric toothbrush charger. I can see a possible mechanism for the first two devices - the periodic connecting and disconnecting at radio frequencies of two large metalic structures via the power supply rectifier diodes. The power wiring is one structure. For the VCR, the other structure is the cable TV wiring, and for the dishwasher the pumbing is the other structure. The electric toothbrush charger must do it all through the wiring. This is definitely modulation - the radio station having the worst modulation goes off the air for about 1 second at dawn and dusk while they change antenna pattern, and the interference goes away. It the problem were emissions, the interference would be very audible with the radio station off the air. I haven't had the time to try filtering the power line at the devices to address the problem, but that is not what this posting is about. My question: Are there any regulatory standards that address modulation interference like this? This is a very unusual phenomenon. If it is the 'modulation hum' of tube receiver days, it is due to a lack of immunity in the receiver. Have you tried other radios? IIRC, h.f. noise generated by rectifiers and thus deeply modulated at power frequency gets on to the mains supply and, due to inadequate filtering or some capacitive coupling in the receiver, gets on to the local oscillator supply or the a.g.c. line. -- 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 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: Laser safety questions
I read in !emc-pstc that Gandler, Mark mgand...@ciena.com wrote (in 4fb204c0ca96d54aa7805b3715620bdd13b...@w2ksjexg02.oni.com) about 'Laser safety questions' on Tue, 12 Nov 2002: According to the new revision of IEC 60825-1 (2001-08) , there are following laser products classes: 1, 1M, 2, 2M , 3R , 3B and 4, instead of 1, 2 , 3A, 3B and 4 per previous revision. Question # 1 : should we change the labeling, let's say from 3A to 3R? Is it any timetable for implementation? There are NO timetables associated with *IEC* standards, which are purely voluntary. There *IS* a timetable associated with an EN version, if there is one. -- 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 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: TC77b Rewrite of 61000-4-2 and 61000-4-4
I read in !emc-pstc that Pettit, Ghery ghery.pet...@intel.com wrote (in d9223eb959a5d511a98f00508b68c20c12515...@orsmsx108.jf.intel.com) about 'TC77b Rewrite of 61000-4-2 and 61000-4-4' on Tue, 12 Nov 2002: As a 3 year maintenance cycle was imposed on CISPR 24 in September, there won't be any changes for the ITE world until 2006 or so. There can be, if anyone makes a strong enough case for an appeal to the SMB for permission to 'break' the approved maintenance cycle. But in practice, 3 years is about the shortest time in which a maintenance cycle can be completed. That is why I'm trying to introduce 'interpretations' from the 'safety' sector into the 'EMC sector. While they don't replace amendments, they do allow a certain flexibility in coping with innovations. -- 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 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: Directive 97/24/EC
I read in !emc-pstc that Luke Turnbull luke.turnb...@trw.com wrote (in sdd0c5d9@mail2-shrluk.trw.com) about 'Directive 97/24/EC' on Tue, 12 Nov 2002: Does anyone know where I might find a pdf version of this document. The text is public domain, but the version that is on the europa website doesn't have the pictures. I've complained about that, with no effect AFAIK. -- 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 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: EN60950:2000 EN60950-1 last dates of manufacture
I read in !emc-pstc that Peter L. Tarver peter.tar...@sanmina-sci.com wrote (in nebbkemlgllmjofmopleoehdebaa.peter.tar...@sanmina-sci.com) about 'EN60950:2000 EN60950-1 last dates of manufacture' on Tue, 12 Nov 2002: It would be a good thing (tm) if Subclause 4.5 of the Guide to the Implementation of Directives Based on New Approach and Global Approach (Blue Guide) made such a clear and unambiguous statement. Perhaps you can make this recommendation to your acquaintance. In my report to the group, I included a quote from my e-mail thanking my contact for his response, saying that the Commission should publish a document about the meaning of docopocoss. He has now replied that he has forwarded the proposal to the Commission. -- 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 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
