Re: [PSES] EMC and RTTE directive - out of scope because of power levels?
Hi John, Quartz Watches are exempted from the EMC Directive, according to the guide for the EMC Directive, see Guide for the EMC Directive 2004/108/EC page 14 - 15: http://ec.europa.eu/enterprise/sectors/electrical/files/emc_guide__updated_2 0100208_v3_en.pdf Best regards Helge Knudsen Denmark -Original Message- From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of John Woodgate Sent: 26. januar 2012 04:43 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: EMC and RTTE directive - out of scope because of power levels? In message <7b3d1875a9a53142ab5d421ee97d0e6003bbb...@ccsexchange.ccsdomain.ccsemc.co m>, dated Wed, 25 Jan 2012, Michael Heckrotte writes: >Years ago I recall discussions about electronic wristwatches and FCC >compliance; the power drawn from the watch battery was less than the >output power of an emission that would just pass the Class B limit >therefore compliance was inherent and no EMC testing was required. I >don?t know if this was ever codified. It wasn't codified into the EMC Directive or the Guide, but it is a very good approach and would probably convince in Europe. I suspect it's not inconsistent with my suggestion that actual emission 40 dB below the relevant limit is a criterion for 'benign' that some would demand. > >Extending this concept to a radio would give new meaning to a >flea-powered transmitter. Indeed, but EMC basically doesn't care whether the radiator is intentional or not (except on-channel, of course); what is sauce for the wristwatch is sauce for the radio. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK Some people who are peeling the finch of the financial crisis are thinking of biting a rook. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald: - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] EMC and RTTE directive - out of scope because of power levels?
In message <7b3d1875a9a53142ab5d421ee97d0e6003bbb...@ccsexchange.ccsdomain.ccsemc.co m>, dated Wed, 25 Jan 2012, Michael Heckrotte writes: Years ago I recall discussions about electronic wristwatches and FCC compliance; the power drawn from the watch battery was less than the output power of an emission that would just pass the Class B limit therefore compliance was inherent and no EMC testing was required. I don?t know if this was ever codified. It wasn't codified into the EMC Directive or the Guide, but it is a very good approach and would probably convince in Europe. I suspect it's not inconsistent with my suggestion that actual emission 40 dB below the relevant limit is a criterion for 'benign' that some would demand. Extending this concept to a radio would give new meaning to a flea-powered transmitter. Indeed, but EMC basically doesn't care whether the radiator is intentional or not (except on-channel, of course); what is sauce for the wristwatch is sauce for the radio. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK Some people who are peeling the finch of the financial crisis are thinking of biting a rook. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] EMC and RTTE directive - out of scope because of power levels?
From Part 15: Section 15.103 Exempted devices. The following devices are subject only to the general conditions of operation in Sections 15.5 and 15.29 and are exempt from the specific technical standards and other requirements contained in this Part. The operator of the exempted device shall be required to stop operating the device upon a finding by the Commission or its representative that the device is causing harmful interference. Operation shall not resume until the condition causing the harmful interference has been corrected. Although not mandatory, it is strongly recommended that the manufacturer of an exempted device endeavor to have the device meet the specific technical standards in this Part. [SNIPPED] *(f) Digital devices that have a power consumption not exceeding 6 nW. * Cortland Richmond On 1/25/2012 1842, Michael Heckrotte wrote: Years ago I recall discussions about electronic wristwatches and FCC compliance; the power drawn from the watch battery was less than the output power of an emission that would just pass the Class B limit therefore compliance was inherent and no EMC testing was required. I don't know if this was ever codified. Extending this concept to a radio would give new meaning to a flea-powered transmitter. Best Regards, Mike - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] EMC and RTTE directive - out of scope because of power levels?
Years ago I recall discussions about electronic wristwatches and FCC compliance; the power drawn from the watch battery was less than the output power of an emission that would just pass the Class B limit therefore compliance was inherent and no EMC testing was required. I don't know if this was ever codified. Extending this concept to a radio would give new meaning to a flea-powered transmitter. Best Regards, Mike From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Crane, Lauren Sent: Wednesday, January 25, 2012 1:31 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: EMC and RTTE directive - out of scope because of power levels? With regard to the EU EMC Directive, can anyone recommend a rule of thumb for when it can be said that equipment is a) incapable of generating or contributing to electromagnetic emissions which exceed a level allowing radio and telecommunication equipment and other equipment to operate as intended; and b) it will operate without unacceptable degradation in the presence of the electromagnetic disturbance normally consequent upon its intended use? My rough guess for a) is that it is fair to claim if the equipment emissions are below 20% of the limit line for the same group & class of equipment. My rough guess for b) is that it is fair to claim if the equipment has operated in its intended environment without known errors due to electromagnetic disturbance. The thesis I am exploring here is that an known EMC emitter is not necessarily in scope of the EMC directive if Article 1.3 is valid, and what is a sound way to test its validity. Although I cannot find it explicitly in the RTTE directive, I wonder if there is a similar concept in practice - radio equipment having such low power levels such that they are considered benign? Regards, Lauren Crane (mr.) KLA-Tencor | Chief Engineer Staff Corp. Product Compliance Mgr. = - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher David Heald - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] EMC and RTTE directive - out of scope because of power levels?
In message m>, dated Wed, 25 Jan 2012, "Crane, Lauren" writes: With regard to the EU EMC Directive, can anyone recommend a rule of thumb for when it can be said that equipment is a) incapable of generating or contributing to electromagnetic emissions which exceed a level allowing radio and telecommunication equipment and other equipment to operate as intended; and b) it will operate without unacceptable degradation in the presence of the electromagnetic disturbance normally consequent upon its intended use? No, the authorities balked at it and 'leave it to the Courts to decide'. My rough guess for a) is that it is fair to claim if the equipment emissions are below 20% of the limit line for the same group & class of equipment. I don't think you will get away with that (-14 dB(limit)) with the EMC zealots. I should think 40 rather than 14 would be needed to satisfy the zealots. My rough guess for b) is that it is fair to claim if the equipment has operated in its intended environment without known errors due to electromagnetic disturbance. I think you might succeed with that. The thesis I am exploring here is that an known EMC emitter is not necessarily in scope of the EMC directive if Article 1.3 is valid, and what is a sound way to test its validity. As I indicated, I doubt there is a 'sound' way. If there was a body of case law Although I cannot find it explicitly in the RTTE directive, I wonder if there is a similar concept in practice ? radio equipment having such low power levels such that they are considered benign? I haven't seen anything like that. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK Some people who are peeling the finch of the financial crisis are thinking of biting a rook. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] Power Amp for IEC 61000-4-16
I don't follow the SWR thing at all, since I wouldn't expect it to be an issue at such small fractions of a wavelength. (but I'm no transmission line expert) I can see how -40dB level of any harmonic well past 150kHz could a challenge. Audio amplifier of old (Class AB analogue with one that one fb loop) used to claim THD < 0.05% to at least 20kHz. So 1% THD out to 150kHz might not be unreachable, at least for those older amps. Slew rate limit might be a gotcha. ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering From: don_borow...@selinc.com To: EMC-PSTC@LISTSERV.IEEE.ORG Date: 01/25/2012 08:09 AM Subject: Re: [PSES] Power Amp for IEC 61000-4-16 Ken- I have not only one, but two amplifiers that start at 10 kHz: an AR 25A100 (25 watts) and an AR 150A100A (150 watts). I only need 15 Vrms (4.5 watts) into a 50 ohm load from the 50 source impedance of the amplifier, so what is the problem? Well, the standard also requires the that source impedance be between 45 and 55 ohms. That doesn't sound so bad until you translate that into SWR (1.1:1 and 1.11:1) and compare that to the 2:1 output impedance specification of the amplifiers. To get a good enough match, I need to add an attenuator to the output of the amplifier. Running the math, one finds that 9 dB of attenuation is needed. I do have a 10 dB high power attenuator. Of course, that means that the amplifier now needs to put out 45 watts to deliver the 4.5 watts into the 50 ohm load. The 25 watt amplifier is out of the running at this point. I was able to simply add a series resistor to (barely) get the output impedance into the 45 to 55 ohm range over 10 kHz to 150 kHz. This would minimize the amount of attenuation. But... That 1% THD spec doesn't seem that bad until one realizes this means that the harmonics need to be better than -40 dBc. Turns out that both amplifiers at their low frequency limits (10 kHz) have increased distortion, though still within their -20 dBc specifications. In fact, even the 150 watt amplifier cannot deliver 4.5 watts with -40 dBc harmonics at 10 kHz into 50 ohms (no attenuator at the output). Audio amps are just fine up to 20 kHz or so, but fall apart rapidly after that. If they can deliver 30 Vrms open circuit (amp rated at more than 112.5 watts into 8 ohms), their distortion goes up rapidly as the feedback loop gain drops at the high frequencies. So what started out seeming to be a fairly simply measurement problem that might require a bit of tweaking turns out to be quite a head-spinner. I blame the standard. The distortion requirement is well beyond what is needed to insure an accurate test signal level. It seems the standard is trying to prevent false failures caused by harmonics. In other standards such as IEC 61000-4-3 radiated immunity (-6 dBc harmonics in the RF field) and IEC 61000-4-6 conducted immunity (-15 dBc harmonics in the test signal), there are statements indicating that the harmonic levels may be high enough to cause false failures and the tester need to exercise care to make sure this is not the case. I personally had to suppress harmonics to -60 dBc in the GSM band when testing a GSM clock to IEC 61000-4-3 radiated immunity, 80-1000 MHz. It would be absurd to require -60 dBc harmonics as a general requirement for radiated immunity testing. Note: I have made my views known to at least one US member of the relevant IEC committee. Donald Borowski EMC Compliance Engineer Schweitzer Engineering Labs Pullman, WA, USA From: Ken Javor To: Date: 01/24/2012 08:33 PM Subject:Re: [PSES] Power Amp for IEC 61000-4-16 Sent by:emc-p...@ieee.org I?m not familiar with the 61000-4-16 standard and its limit. If the limit is flat and requires 30 Vrms oc output at 150 kHz, that would indeed be a problem if you had to do it with an audio amplifier, but of course that isn?t necessary. Every lab has a 50 Ohm output amplifier that starts at 10 kHz. So the audio amp need only have flat performance out to 10 kHz, and they will all do that. Ken Javor Phone: (256) 650-5261 From: Date: Tue, 24 Jan 2012 17:06:27 -0800 To: Subject: Re: [PSES] Power Amp for IEC 61000-4-16 1% THD all the way to 150kHz? Just wondering if the older analogue amps could do that, not to mention the (Class D?) amplifiers of today. Why not just put a 50 ohm resistor in series with the amplifier output. Audio amps should have no trouble operating into an open circuit. A 100W/ch amp should satisfy the 30Vrms requirement, but the THD might be a problem at the highest frequencies. ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering From: Ken Javor To: EMC-PSTC@LIST
Re: [PSES] power plugs and outlets
i.e. basic insulation remains after failure of the grounding means. (e.g. a metal chassis still touch-safe) ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering From: "ce-test, qualified testing bv - Gert Gremmen" To: EMC-PSTC@LISTSERV.IEEE.ORG Date: 01/25/2012 12:09 PM Subject: Re: [PSES] power plugs and outlets Oh I forgot: “single fault” refers to a safety test where the test agency voluntarily removes ground from an EUT to verify that the EUT still complies with the safety requirements. (but with only 1 safety layer remaining) Gert Gremmen Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens ce-test, qualified testing bv - Gert Gremmen Verzonden: woensdag 25 januari 2012 20:51 Aan: Mark Gandler; emc-pstc@LISTSERV.IEEE.ORG Onderwerp: RE: power plugs and outlets No. Has no ground in French sockets. Creating a single fault on purpose… what do you think :<) ??? http://img.hisupplier.com/var/userImages/old/qingtai/qingtai$722162956.jpg this is the socket in France. I’d go for the cee7/7 , suitable all over Europe for Class I but some non-euro (€) territories ;<)) such as the UK , Italy and Switzerland. UK : http://www.eco-drive.co.uk/images/socket.jpg and for more sockets/plugs : http://www.powercords.co.uk/standard.htm (Not related) Gert Gremmen ce-test qualified testing Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens Mark Gandler Verzonden: woensdag 25 januari 2012 19:12 Aan: emc-pstc@LISTSERV.IEEE.ORG Onderwerp: power plugs and outlets Can you sell CEE 7/4 outlet in France? - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to < emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher David Heald - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to < emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher David Heald __ This email has been scanned by the Symantec Email Security.cloud service. __ - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to < emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher David Heald - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pse
[PSES] EMC and RTTE directive - out of scope because of power levels?
With regard to the EU EMC Directive, can anyone recommend a rule of thumb for when it can be said that equipment is a) incapable of generating or contributing to electromagnetic emissions which exceed a level allowing radio and telecommunication equipment and other equipment to operate as intended; and b) it will operate without unacceptable degradation in the presence of the electromagnetic disturbance normally consequent upon its intended use? My rough guess for a) is that it is fair to claim if the equipment emissions are below 20% of the limit line for the same group & class of equipment. My rough guess for b) is that it is fair to claim if the equipment has operated in its intended environment without known errors due to electromagnetic disturbance. The thesis I am exploring here is that an known EMC emitter is not necessarily in scope of the EMC directive if Article 1.3 is valid, and what is a sound way to test its validity. Although I cannot find it explicitly in the RTTE directive, I wonder if there is a similar concept in practice - radio equipment having such low power levels such that they are considered benign? Regards, Lauren Crane (mr.) KLA-Tencor | Chief Engineer Staff Corp. Product Compliance Mgr. = - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] power plugs and outlets
In message , dated Wed, 25 Jan 2012, "ce-test, qualified testing bv - Gert Gremmen" writes: No. Has no ground in French sockets. That projecting pin is the ground. Or should be. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK Some people who are peeling the finch of the financial crisis are thinking of biting a rook. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] power plugs and outlets
Oh I forgot: “single fault” refers to a safety test where the test agency voluntarily removes ground from an EUT to verify that the EUT still complies with the safety requirements. (but with only 1 safety layer remaining) Gert Gremmen Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens ce-test, qualified testing bv - Gert Gremmen Verzonden: woensdag 25 januari 2012 20:51 Aan: Mark Gandler; emc-pstc@LISTSERV.IEEE.ORG Onderwerp: RE: power plugs and outlets No. Has no ground in French sockets. Creating a single fault on purpose… what do you think :<) ??? http://img.hisupplier.com/var/userImages/old/qingtai/qingtai$722162956.jpg this is the socket in France. I’d go for the cee7/7 , suitable all over Europe for Class I but some non-euro (€) territories ;<)) such as the UK , Italy and Switzerland. UK : http://www.eco-drive.co.uk/images/socket.jpg and for more sockets/plugs : http://www.powercords.co.uk/standard.htm (Not related) Gert Gremmen ce-test qualified testing Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens Mark Gandler Verzonden: woensdag 25 januari 2012 19:12 Aan: emc-pstc@LISTSERV.IEEE.ORG Onderwerp: power plugs and outlets Can you sell CEE 7/4 outlet in France? - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher David Heald - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher David Heald - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] FCC requirements for Inductive Chargers
In message <1327520440.74806.yahoomailclas...@web1109.biz.mail.sk1.yahoo.com>, dated Wed, 25 Jan 2012, Bob Richards writes: Is that the same gallium alloy used in the turbo entabulator? ;-) No, it's 99.99% pure gallium. Otherwise it wouldn't melt when you put it on. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK Some people who are peeling the finch of the financial crisis are thinking of biting a rook. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] FCC requirements for Inductive Chargers
This makes me realise how boring my reply was. I'm sorry. I'll try harder next time. I don't want to be one of those guys in the red shirt who only turns up for one episode and you know he's going to get killed. Michael Derby Regulatory Engineer ACB Europe From: Bob Richards [mailto:b...@toprudder.com] Sent: 25 January 2012 19:41 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] FCC requirements for Inductive Chargers Is that the same gallium alloy used in the turbo entabulator? ;-) --- On Wed, 1/25/12, John Woodgate wrote: From: John Woodgate Subject: Re: FCC requirements for Inductive Chargers To: EMC-PSTC@LISTSERV.IEEE.ORG Date: Wednesday, January 25, 2012, 2:18 PM In message http://us.mc1616.mail.yahoo.com/mc/compose?to=B4C40DB49FD3404C80870094CE1B0 e...@tamuracorp.com> >, dated Wed, 25 Jan 2012, Brian Oconnell http://us.mc1616.mail.yahoo.com/mc/compose?to=oconne...@tamuracorp.com> > writes: > When human exposure mentioned, I think about Star Trek's 'subnucleonic radiation' - will CISPR32 address these limits? Yes, in the 6th edition, published in 2042. I've already commissioned a supply of gallium foil helmets to screen against the Higgs field. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK Some people who are peeling the finch of the financial crisis are thinking of biting a rook. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to http://us.mc1616.mail.yahoo.com/mc/compose?to=emc-p...@ieee.org> > All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas http://us.mc1616.mail.yahoo.com/mc/compose?to=emcp...@radiusnorth.net> > Mike Cantwell http://us.mc1616.mail.yahoo.com/mc/compose?to=mcantw...@ieee.org> > For policy questions, send mail to: Jim Bacher: http://us.mc1616.mail.yahoo.com/mc/compose?to=j.bac...@ieee.org> > David Heald: http://us.mc1616.mail.yahoo.com/mc/compose?to=dhe...@gmail.com> > - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher David Heald - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] FCC requirements for Inductive Chargers
Hello, Please note that not all of these wireless chargers would be Part 15 (47CFR15, as stated). Some might be Part 18, depending on the operation. I think you'd need to look at the operation of the charger and see if any form of 'handshaking' is taking place; even if it's just a recognition signal. If it is, you could say that's data or communication and Part 15 could apply. If not, this could be a Part 18 device. It's a little like the European debate of "Does the EMC Directive or R&TTE Directive apply?" You need to ask yourself if it is just using RF for a process, or if there is some form of communication taking place. Thanks, Michael. Michael Derby Regulatory Engineer ACB Europe -Original Message- From: Brian Oconnell [mailto:oconne...@tamuracorp.com] Sent: 25 January 2012 19:03 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] FCC requirements for Inductive Chargers ICNIRP 29CFR1926 29CFR1910 ANSI C95.x 47CFR15 CISPR 11,12,14,22 When human exposure mentioned, I think about Star Trek's 'subnucleonic radiation' - will CISPR32 address these limits? Brian -Original Message- From: emc-p...@ieee.org [mailto:emc-p...@ieee.org]On Behalf Of Moshe Henig Sent: Wednesday, January 25, 2012 10:19 AM To: emc-pstc-requ...@listserv.ieee.org; emc-p...@ieee.org; EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: FCC requirements for Inductive Chargers Thanks group, But what are the FCC requirements for wireless chargers that does not comply with WPC? Thanks Moshe 2012/1/23 Moshe Henig Dear Group, What are FCC requirements for Mobile Phone Battery Inductive Charger and what are the conditions? Thanks Moshe Henig Dipl. Ing. NCE SMIEEE iNarte Certified EMC engineer EMC and Safety consultant Mobile +972 52 8951449 Skype mhenig he...@bezeqint.net - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald: - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] power plugs and outlets
No. Has no ground in French sockets. Creating a single fault on purpose… what do you think :<) ??? http://img.hisupplier.com/var/userImages/old/qingtai/qingtai$722162956.jpg this is the socket in France. I’d go for the cee7/7 , suitable all over Europe for Class I but some non-euro (€) territories ;<)) such as the UK , Italy and Switzerland. UK : http://www.eco-drive.co.uk/images/socket.jpg and for more sockets/plugs : http://www.powercords.co.uk/standard.htm (Not related) Gert Gremmen ce-test qualified testing Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens Mark Gandler Verzonden: woensdag 25 januari 2012 19:12 Aan: emc-pstc@LISTSERV.IEEE.ORG Onderwerp: power plugs and outlets Can you sell CEE 7/4 outlet in France? - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher David Heald - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] FCC requirements for Inductive Chargers
Is that the same gallium alloy used in the turbo entabulator? ;-) --- On Wed, 1/25/12, John Woodgate wrote: From: John Woodgate Subject: Re: FCC requirements for Inductive Chargers To: EMC-PSTC@LISTSERV.IEEE.ORG Date: Wednesday, January 25, 2012, 2:18 PM In message , dated Wed, 25 Jan 2012, Brian Oconnell writes: > When human exposure mentioned, I think about Star Trek's 'subnucleonic > radiation' - will CISPR32 address these limits? Yes, in the 6th edition, published in 2042. I've already commissioned a supply of gallium foil helmets to screen against the Higgs field. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK Some people who are peeling the finch of the financial crisis are thinking of biting a rook. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald: - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] Power Amp for IEC 61000-4-16
Don, 1% does sound extreme to me, but I am not familiar with the intent of this requirement. This does remind me about my experience years ago during an audit to the automotive tri-plate immunity test. We had to run an artifact that was supplied by the auditors at two levels, 50v/m and 200 v/m. At each frequency we had to read the output voltage of an RF detector that was the test artifact. At some point in the frequency range, the output voltage tracked more than 12dB higher for the 200v/m test. The auditor said we had a harmonic output problem with our amp. I discovered that the amp had better than -20dBc at the higher level, which met the requirements of the standard. However, the test artifact had something like 40dB gain from the fundamental to the second harmonic through part of the frequency range, and that is why the numbers did not track. IMHO, if a product failed due to the harmonics, it would certainly fail by an even wider margin when the fundamental moved up to the same frequency where the harmonic had caused the problem. But, it was a finding in the audit that we had to address, so we ended up using a 2500w amp instead of our 200w amp. Way overkill, but was the quickest corrective action for the audit. Regarding your GSM clock situation, I have not had to deal with anything like that (yet) but I have wondered if, instead of stepping the normal 1% step size, would it be possible to pick the fundamental frequencies such that the harmonics would fall outside of the sensitive area. Of course, this would assume that the frequency response around the sensitive area was narrow enough that it would fall into a 1% window. Bob R. --- On Wed, 1/25/12, don_borow...@selinc.com wrote: From: don_borow...@selinc.com Subject: Re: [PSES] Power Amp for IEC 61000-4-16 To: emc-p...@ieee.org Cc: ken.ja...@emccompliance.com Date: Wednesday, January 25, 2012, 11:07 AM Ken- I have not only one, but two amplifiers that start at 10 kHz: an AR 25A100 (25 watts) and an AR 150A100A (150 watts). I only need 15 Vrms (4.5 watts) into a 50 ohm load from the 50 source impedance of the amplifier, so what is the problem? Well, the standard also requires the that source impedance be between 45 and 55 ohms. That doesn't sound so bad until you translate that into SWR (1.1:1 and 1.11:1) and compare that to the 2:1 output impedance specification of the amplifiers. To get a good enough match, I need to add an attenuator to the output of the amplifier. Running the math, one finds that 9 dB of attenuation is needed. I do have a 10 dB high power attenuator. Of course, that means that the amplifier now needs to put out 45 watts to deliver the 4.5 watts into the 50 ohm load. The 25 watt amplifier is out of the running at this point. I was able to simply add a series resistor to (barely) get the output impedance into the 45 to 55 ohm range over 10 kHz to 150 kHz. This would minimize the amount of attenuation. But... That 1% THD spec doesn't seem that bad until one realizes this means that the harmonics need to be better than -40 dBc. Turns out that both amplifiers at their low frequency limits (10 kHz) have increased distortion, though still within their -20 dBc specifications. In fact, even the 150 watt amplifier cannot deliver 4.5 watts with -40 dBc harmonics at 10 kHz into 50 ohms (no attenuator at the output). Audio amps are just fine up to 20 kHz or so, but fall apart rapidly after that. If they can deliver 30 Vrms open circuit (amp rated at more than 112.5 watts into 8 ohms), their distortion goes up rapidly as the feedback loop gain drops at the high frequencies. So what started out seeming to be a fairly simply measurement problem that might require a bit of tweaking turns out to be quite a head-spinner. I blame the standard. The distortion requirement is well beyond what is needed to insure an accurate test signal level. It seems the standard is trying to prevent false failures caused by harmonics. In other standards such as IEC 61000-4-3 radiated immunity (-6 dBc harmonics in the RF field) and IEC 61000-4-6 conducted immunity (-15 dBc harmonics in the test signal), there are statements indicating that the harmonic levels may be high enough to cause false failures and the tester need to exercise care to make sure this is not the case. I personally had to suppress harmonics to -60 dBc in the GSM band when testing a GSM clock to IEC 61000-4-3 radiated immunity, 80-1000 MHz. It would be absurd to require -60 dBc harmonics as a general requirement for radiated immunity testing. Note: I have made my views known to at least one US member of the relevant IEC committee. Donald Borowski EMC Compliance Engineer Schweitzer Engineering Labs Pullman, WA, USA From: Ken Javor To: Date: 01/24/2012 08:33 PM Subject: Re: [PSES] Power Amp for IEC 61000-4-16 Sent by: emc-p...@ieee.org I?m not familiar with the 61000-4-16 standard and its limit
Re: [PSES] FCC requirements for Inductive Chargers
In message , dated Wed, 25 Jan 2012, Brian Oconnell writes: When human exposure mentioned, I think about Star Trek's 'subnucleonic radiation' - will CISPR32 address these limits? Yes, in the 6th edition, published in 2042. I've already commissioned a supply of gallium foil helmets to screen against the Higgs field. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK Some people who are peeling the finch of the financial crisis are thinking of biting a rook. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] FCC requirements for Inductive Chargers
ICNIRP 29CFR1926 29CFR1910 ANSI C95.x 47CFR15 CISPR 11,12,14,22 When human exposure mentioned, I think about Star Trek's 'subnucleonic radiation' - will CISPR32 address these limits? Brian -Original Message- From: emc-p...@ieee.org [mailto:emc-p...@ieee.org]On Behalf Of Moshe Henig Sent: Wednesday, January 25, 2012 10:19 AM To: emc-pstc-requ...@listserv.ieee.org; emc-p...@ieee.org; EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: FCC requirements for Inductive Chargers Thanks group, But what are the FCC requirements for wireless chargers that does not comply with WPC? Thanks Moshe 2012/1/23 Moshe Henig Dear Group, What are FCC requirements for Mobile Phone Battery Inductive Charger and what are the conditions? Thanks Moshe Henig Dipl. Ing. NCE SMIEEE iNarte Certified EMC engineer EMC and Safety consultant Mobile +972 52 8951449 Skype mhenig he...@bezeqint.net - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] FCC requirements for Inductive Chargers
Thanks group, But what are the FCC requirements for wireless chargers that does not comply with WPC? Thanks Moshe 2012/1/23 Moshe Henig > Dear Group, > > What are FCC requirements for Mobile Phone Battery Inductive Charger and > what are the conditions? > > Thanks > > > Moshe Henig Dipl. Ing. > > NCE SMIEEE > > iNarte Certified EMC engineer > > EMC and Safety consultant > > Mobile +972 52 8951449 > > Skype mhenig > > he...@bezeqint.net > - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
[PSES] power plugs and outlets
Can you sell CEE 7/4 outlet in France? - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] Power Amp for IEC 61000-4-16
Ken- I have not only one, but two amplifiers that start at 10 kHz: an AR 25A100 (25 watts) and an AR 150A100A (150 watts). I only need 15 Vrms (4.5 watts) into a 50 ohm load from the 50 source impedance of the amplifier, so what is the problem? Well, the standard also requires the that source impedance be between 45 and 55 ohms. That doesn't sound so bad until you translate that into SWR (1.1:1 and 1.11:1) and compare that to the 2:1 output impedance specification of the amplifiers. To get a good enough match, I need to add an attenuator to the output of the amplifier. Running the math, one finds that 9 dB of attenuation is needed. I do have a 10 dB high power attenuator. Of course, that means that the amplifier now needs to put out 45 watts to deliver the 4.5 watts into the 50 ohm load. The 25 watt amplifier is out of the running at this point. I was able to simply add a series resistor to (barely) get the output impedance into the 45 to 55 ohm range over 10 kHz to 150 kHz. This would minimize the amount of attenuation. But... That 1% THD spec doesn't seem that bad until one realizes this means that the harmonics need to be better than -40 dBc. Turns out that both amplifiers at their low frequency limits (10 kHz) have increased distortion, though still within their -20 dBc specifications. In fact, even the 150 watt amplifier cannot deliver 4.5 watts with -40 dBc harmonics at 10 kHz into 50 ohms (no attenuator at the output). Audio amps are just fine up to 20 kHz or so, but fall apart rapidly after that. If they can deliver 30 Vrms open circuit (amp rated at more than 112.5 watts into 8 ohms), their distortion goes up rapidly as the feedback loop gain drops at the high frequencies. So what started out seeming to be a fairly simply measurement problem that might require a bit of tweaking turns out to be quite a head-spinner. I blame the standard. The distortion requirement is well beyond what is needed to insure an accurate test signal level. It seems the standard is trying to prevent false failures caused by harmonics. In other standards such as IEC 61000-4-3 radiated immunity (-6 dBc harmonics in the RF field) and IEC 61000-4-6 conducted immunity (-15 dBc harmonics in the test signal), there are statements indicating that the harmonic levels may be high enough to cause false failures and the tester need to exercise care to make sure this is not the case. I personally had to suppress harmonics to -60 dBc in the GSM band when testing a GSM clock to IEC 61000-4-3 radiated immunity, 80-1000 MHz. It would be absurd to require -60 dBc harmonics as a general requirement for radiated immunity testing. Note: I have made my views known to at least one US member of the relevant IEC committee. Donald Borowski EMC Compliance Engineer Schweitzer Engineering Labs Pullman, WA, USA From: Ken Javor To: Date: 01/24/2012 08:33 PM Subject:Re: [PSES] Power Amp for IEC 61000-4-16 Sent by:emc-p...@ieee.org I?m not familiar with the 61000-4-16 standard and its limit. If the limit is flat and requires 30 Vrms oc output at 150 kHz, that would indeed be a problem if you had to do it with an audio amplifier, but of course that isn?t necessary. Every lab has a 50 Ohm output amplifier that starts at 10 kHz. So the audio amp need only have flat performance out to 10 kHz, and they will all do that. Ken Javor Phone: (256) 650-5261 From: Date: Tue, 24 Jan 2012 17:06:27 -0800 To: Subject: Re: [PSES] Power Amp for IEC 61000-4-16 1% THD all the way to 150kHz? Just wondering if the older analogue amps could do that, not to mention the (Class D?) amplifiers of today. Why not just put a 50 ohm resistor in series with the amplifier output. Audio amps should have no trouble operating into an open circuit. A 100W/ch amp should satisfy the 30Vrms requirement, but the THD might be a problem at the highest frequencies. ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering From: Ken Javor To: EMC-PSTC@LISTSERV.IEEE.ORG Date: 01/24/2012 03:45 PM Subject: Re: [PSES] Power Amp for IEC 61000-4-16 Any decent quality audio power amplifier will have THD below 1% these days. Consider using a step-up transformer such as the Solar Electronics 8810-1. It is designed to impedance match from 1.5 Ohms to 50 Ohms, and can handle 200 Watts. That will more than suffice for your needs. Ken Javor Phone: (256) 650-5261 > From: > Date: Tue, 24 Jan 2012 15:30:55 -0800 > To: > Subject: Power Amp for IEC 61000-4-16 > > A new testing requirement for some of my company's products is IEC > 61000-4-16 Conducted Common Mode Disturbances. I need to test from 10 kHz > to 150 kHz. > > I have a good low distortion signal source, but I need a power amplifier > to give me the signal at the test level: 30 Vrms open circuit, 50±5
