Re: Fw: working voltage measurement
One can also use a pair of probes known to be well balanced and take the difference between the A and B channels, or use a differential input accessory or plugin. There is then no possibility of high-voltage on the instrument chassis. Cortland (my own thoughts, and nor those of my employer) Rich Nute wrote: There are two ways to minimize the effect of the common side of the scope from affecting the waveform: 1) If you are using a mains-operated scope, supply the SMPS from an isolating transformer where both supply conductors are isolated from ground. In this way, you can connect the scope common lead to any point in the SMPS with minimum effect on the waveform. 2) Use a battery-operated scope such as the Fluke Scopemeter. You can connect the scope common to any point in the SMPS with minimum effect on the wavefrom --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: surges on 24VAC
I read in !emc-pstc that Mavis, Robert rma...@pelco.com wrote (in B2CC0E0F2C10D511B86600B0D0689842024F816C@localhost.pelco1) about 'surges on 24VAC', on Fri, 21 Dec 2001: The AC Mains test is just that AC Mains. The Definition of AC mains is basically what comes out of the wall. Since the product is 24VAC it falls under low voltage/signal lines. Test is as a signal line. No, the standard uses the term 'a.c. power port' in Table 4. It says noting about 'mains'. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: surges on 24VAC
If the 24V AC is generated via a Class II Direct Plug-In power pack, wouldn't the test be run 'through' the power pack - the power pack plugged into the outlet on the surge tester? The power pack runs off of AC Mains. For argument sake, what's the difference of that scenario as compared to having to test a product which is configured with an IEC 320 power entry module through which a 24V AC transformer inside the product receives it's AC Mains? The functional circuit operates off of 24V AC, but the primary power is AC Mains - whether it's supplied through a line cord/power entry module combo or a direct plug-in transformer. My opinion only . . . John Juhasz Fiber Options Bohemia, NY -Original Message- From: Mavis, Robert [mailto:rma...@pelco.com] Sent: Friday, December 21, 2001 1:46 PM To: Jennifer Banh; emc-p...@majordomo.ieee.org Subject: RE: surges on 24VAC The AC Mains test is just that AC Mains. The Definition of AC mains is basically what comes out of the wall. Since the product is 24VAC it falls under low voltage/signal lines. Test is as a signal line. -Original Message- From: Jennifer Banh [mailto:jb...@bb-elec.com] Sent: Monday, December 17, 2001 11:44 AM To: emc-p...@majordomo.ieee.org Subject: surges on 24VAC Hello everyone, I am currently trying to test a product of ours that falls under 50082-1 generic standard for light industrial equipment. Our problem is that we have a 24VAC power input port. The generic standard calls out for EN 61000-4-5 on AC power input ports. After looking at EN 61000-4-5 it seems that it is intended for AC mains voltages, but I couldn't find anything that says a 24VAC input is exempt from this test. I am looking for outside opinions on whether this test is truly applicable. Thanks, Jennifer Banh BTW, we already tried just testing to the spec, and failed. Any suggestions on how to protect against this test would also be appreciated. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: High Frequency Pre-amp
Just a reminderalways make certain that no signal gets in to saturate, or even start to overdrive, your amplifier at frequencies you're not looking at. - Robert - Robert A. Macy, PEm...@california.com 408 286 3985 fx 408 297 9121 AJM International Electronics Consultants 619 North First St, San Jose, CA 95112 -Original Message- From: Ken Javor ken.ja...@emccompliance.com To: rehel...@mmm.com rehel...@mmm.com; emc-p...@majordomo.ieee.org emc-p...@majordomo.ieee.org List-Post: emc-pstc@listserv.ieee.org Date: Friday, December 21, 2001 11:42 AM Subject: Re: High Frequency Pre-amp MITEQ and Mini-Circuits come to mind for octave and multi-octave band amps. HP (Agilent) makes the the 8348A covering 1 - 26.5 GHz around $14 K. The HP model has a 10 dB noise figure and 25 dB gain below 20 GHz. With MITEQ you can pick your noise figure and gain from a large variety of models. Mini-Circuits is the low price leader, I saw amps up to 8 GHz but you would need several models and the price will still likely be less than with the others. If you are using an HP8566 or similar model which uses harmonic mixing above 2 GHz then you need enough gain to push the signal above the degraded noise floor. -- From: rehel...@mmm.com To: emc-p...@majordomo.ieee.org Subject: High Frequency Pre-amp Date: Fri, Dec 21, 2001, 10:16 AM This question may have recently posted but I'm not able to search the archives so I'll ask again. We have an immediate need for a pre-amp above 1000 MHz. Would you be so kind as to let me know what brands/models and frequency range you are using. Any pro/con insights would be welcome as well. Please contact me on or off-line. Thanks, Bob Heller 3M Product Safety, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: power supply to GOST 30429-96
Low frequency conducted noise is usually generated by the periodic demand on the energy storage cap (greatly, greatly affected by esr). This noise is differential and no y-cap (unless it's so large it becomes a killer size, and then not really) will stomp on it. Your first problem (conducted emissions) is trying to get rid of the fundamental of the power supply which can be a bit challenging. You see, the y-caps are low impedance *AND* your noise source is low impedance, so adding y-caps is not going to short out that noise source. The best way to solve your problem is is to use minimum esr caps and, of course, very judicious layout inside the supply. There are external things you can do, but they can get bulky. How much power does this supply take? Do you have control over the manufacturing process at all? Once you've tackled the conducted emissions, we can move on to the radiated emissions. - Robert - Robert A. Macy, PEm...@california.com 408 286 3985 fx 408 297 9121 AJM International Electronics Consultants 619 North First St, San Jose, CA 95112 -Original Message- From: Lou Guerin lgue...@littlefeet-inc.com To: emc-p...@majordomo.ieee.org emc-p...@majordomo.ieee.org List-Post: emc-pstc@listserv.ieee.org Date: Friday, December 21, 2001 10:49 AM Subject: power supply to GOST 30429-96 Dear Fellow EMC workers, I am trying to get a SMPS to pass this GOST standard and am having a devil of a time getting it done. After 3 days of mitigation testing at our local lab we are still out at the low frequency range 10-60kHz and at 15-50MHz. We pass the Class A limits for CISPR 22 but these GOST limits are far more stringent. The power supply is convection cooled in a IP66 box that is powering a repeater. We have been able to determine that the noise is being generated by the power supply and thus far we are not able to suppress all the low frequency and high frequency conducted noise. I have copied the limit requirements below for your review. Has anyone run into this standard before? Is there something we may be overlooking? We are not using a custom supply, this is an off the shelf supply that we are packaging into a IP66 box. The usual fixes didn't seem to work, X and/or Y caps, ferrite beads, inductor. These were applied liberally during the past 3 days. The requirements for EMC of radio equipment in Russia (as well as in several other CIS countries) are set by the standard GOST 30429-96 (Electromagnetic Compatibility of technical equipment. Man-made noise from equipment and apparatus used t6ogether with service receiver systems of civil application. Limits and test methods), according to this standard the following measurement must be done. 1. Conducted Emissions Frequency range Limits, dB(uV) 0.009 MHz - 0.15 MHz U = 90 - 28.9lg(f/0,01) (Quasi-peak) 0.15 MHz - 0.5 MHz U = 66 - 22.7lg(f/0,15) (Quasi-peak) 0.5 MHz - 6 MHz U = 54 - 12.97lg(f/0,5) (Quasi-peak) 6 MHz - 30 MHzU = 40 (Quasi-peak) 30 MHz - 100 MHzU = 48 (Quasi-peak) 40 (Average) This test is done looking at the emissions from the 220 V power cables, using a LISN 2. Radiated Emissions Frequency range Limits, dB(uV/m) 0.01 MHz - 0.15 MHzE = 60 - 20.4lg(f/0.01) 0.15 MHz - 30 MHz E = 37 - 7.39lg(f/0.15) 30 MHz - 100 MHzE = 36 - 21.0lg(f/0.30) 100 MHz - 1000 MHzE = 25 + 20.0lg(f/100) According to GOST 30429-96 this test is done at 3 meters in frequency range 0.01MHz - 30 MHz and at 1 meter in frequency range 30 MHz - 1000 MHz in the screen room. Any help will be eagerly accepted. Best regards and happy holidays, Lou Guerin Agency Approvals Manager Littlefeet, Inc. lgue...@littlefeet-inc.com mailto:lgue...@littlefeet-inc.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: High Frequency Pre-amp
Hello, Miteq JS22-00050800-15-14P with 40 dB gain, 30 to 8000 MHZ Contact Rizwan Syed at 631-439-9458 Miteq AFS66-00102650 - 45-5P-66 40 dB gain Agilent 83006 10 MHz to 26 GHz 20 dB minimum Agilent 83017 The Agilent amplifiers are not as sensitive to ESD as the Miteq's. The gain of the Miteq's make them more useful. Regards, Ken hall -Original Message- From: rehel...@mmm.com [mailto:rehel...@mmm.com] Sent: Friday, December 21, 2001 8:17 AM To: emc-p...@majordomo.ieee.org Subject: High Frequency Pre-amp This question may have recently posted but I'm not able to search the archives so I'll ask again. We have an immediate need for a pre-amp above 1000 MHz. Would you be so kind as to let me know what brands/models and frequency range you are using. Any pro/con insights would be welcome as well. Please contact me on or off-line. Thanks, Bob Heller 3M Product Safety, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: EMI guard bands
The limit for RE is based as I said in an earlier message on the television band rf signal level required to get a specified base band video signal-to-noise ratio. The fact that the interference coupling mechanism is near field is not important, except of course as it affects measurement technique. -- From: Doug McKean dmck...@auspex.com To: EMC-PSTC Discussion Group emc-p...@majordomo.ieee.org Subject: Re: EMI guard bands Date: Fri, Dec 21, 2001, 10:48 AM John Woodgate wrote: I would be suspicious of that; it is a 'near-field' scenario, which means that the emission field strengths are complex and impossible to calculate. The Class B limits are related to a 10 m separation of source and potential victim, and that implies far-field conditions for emissions above about 5 MHz. That's true, but weren't the early measurements for Class B done at 3 meters? - 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: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: High Frequency Pre-amp
MITEQ and Mini-Circuits come to mind for octave and multi-octave band amps. HP (Agilent) makes the the 8348A covering 1 - 26.5 GHz around $14 K. The HP model has a 10 dB noise figure and 25 dB gain below 20 GHz. With MITEQ you can pick your noise figure and gain from a large variety of models. Mini-Circuits is the low price leader, I saw amps up to 8 GHz but you would need several models and the price will still likely be less than with the others. If you are using an HP8566 or similar model which uses harmonic mixing above 2 GHz then you need enough gain to push the signal above the degraded noise floor. -- From: rehel...@mmm.com To: emc-p...@majordomo.ieee.org Subject: High Frequency Pre-amp Date: Fri, Dec 21, 2001, 10:16 AM This question may have recently posted but I'm not able to search the archives so I'll ask again. We have an immediate need for a pre-amp above 1000 MHz. Would you be so kind as to let me know what brands/models and frequency range you are using. Any pro/con insights would be welcome as well. Please contact me on or off-line. Thanks, Bob Heller 3M Product Safety, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
New China Compulsory Certification
From: Cecil A. Gittens Does anyone have information about products that will required EMC certification to meet the new China Compulsory Certification system. It was mentioned that they will host meetings in the future to introduce this new system. Regards Cecil --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: Inquiry of IEC Safety Standard of Antitheft Surveillance Devi ces
Dear Oliver, For the European Market, as per EN50131, the Power supplies for Intruder alarm systems shall comply with the applicable requirements of EN60950, EN60529 (Electrical safety portion). I can not foresee any reason to do not extrapolate this fact to the IEC Standards...60950, 60529. Happy Holidays to all of my VERY PROFESSIONAL COLLEAGUES OF THE MOST PROFESSIONAL AND ELEGANT DISCUSSION GROUP! HAPPY NEW YEAR and HAVE A VERY SAFE AND PROSPEROUS 2002! Respectfully yours, Constantin Constantin Bolintineanu P.Eng. TEPG - DIGITAL SECURITY CONTROLS LTD. 3301 LANGSTAFF Road, L4K 4L2 CONCORD, ONTARIO, CANADA e-mail: bolin...@dscltd.com telephone: 905 760 3000 ext 2568 Visit our web site at www.dscgrp.com -Original Message- From: Oliver Su [mailto:o...@ccsemc.com] Sent: Friday, December 21, 2001 1:26 PM To: 'emc.p...@ieee.org' Subject: Inquiry of IEC Safety Standard of Antitheft Surveillance Devices Hi group, Merry Christmas and Happy New Year! Does anyone know what is IEC Safety Standard of Antitheft Surveillance Device, which is standed at the exit/entrance door of commerical store and department to detect/prevent any merchandise with magnetic piece being stolen. It is wireless and as human's hight, powered by AC120/230V. Best regards, Oliver Su * Oliver Su Compliance Certification Services 561 F Monterey Morgan Hill, CA 95037-9001, USA Tel: (408) 463-0885 x 109 fax: (408) 463-0888 E-mail: o...@ccsemc.com * --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: surges on 24VAC
The AC Mains test is just that AC Mains. The Definition of AC mains is basically what comes out of the wall. Since the product is 24VAC it falls under low voltage/signal lines. Test is as a signal line. -Original Message- From: Jennifer Banh [mailto:jb...@bb-elec.com] Sent: Monday, December 17, 2001 11:44 AM To: emc-p...@majordomo.ieee.org Subject: surges on 24VAC Hello everyone, I am currently trying to test a product of ours that falls under 50082-1 generic standard for light industrial equipment. Our problem is that we have a 24VAC power input port. The generic standard calls out for EN 61000-4-5 on AC power input ports. After looking at EN 61000-4-5 it seems that it is intended for AC mains voltages, but I couldn't find anything that says a 24VAC input is exempt from this test. I am looking for outside opinions on whether this test is truly applicable. Thanks, Jennifer Banh BTW, we already tried just testing to the spec, and failed. Any suggestions on how to protect against this test would also be appreciated. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Inquiry of IEC Safety Standard of Antitheft Surveillance Devices
Hi group, Merry Christmas and Happy New Year! Does anyone know what is IEC Safety Standard of Antitheft Surveillance Device, which is standed at the exit/entrance door of commerical store and department to detect/prevent any merchandise with magnetic piece being stolen. It is wireless and as human's hight, powered by AC120/230V. Best regards, Oliver Su * Oliver Su Compliance Certification Services 561 F Monterey Morgan Hill, CA 95037-9001, USA Tel: (408) 463-0885 x 109 fax: (408) 463-0888 E-mail: o...@ccsemc.com * --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: RJ45 filtered -possible solution
Reginald, I was somewhat pessimistic about your chances of finding what you were looking for. I just got some literature today which mentions a company called Lumburg. They have some bulkhead Ethernet adapters; the likes of which I haven't seen from anyone else. Try www.lumbergusa.com. Hope this helps. Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: Chris Maxwell Sent: Friday, December 21, 2001 8:20 AM To: 'Knighten, Jim L'; Reginald Henry; emc-p...@majordomo.ieee.org Subject: RE: RJ45 filtered connector Happy Holidays Reginald, Corcom also makes flanged/filtered RJ45 (or 8 pin modular, if you prefer) jacks. I have seen many manufacturers that filter these jacks (Amphenol, Amp, Corcom, possibly LZR...). Most of them have already been mentioned. Problem is, I'm not sure what you mean by a bulkhead mount. If you are looking for a connector that has a built in mounting mechanism that you can just fasten to the wall...I think that you'll be disappointed. The connectors that I've seen are designed for PCB mounting. Of course, I haven't seen everything and I hope you find what you're looking for. If not, and if you really are determined to have a bulkhead RJ45; I would suggest rigging up your own bulkhead connector using one of the flanged and filtered models from Corcom or Regal. If this won't work, I like the suggestion made in another posting to use either a filtered Dsub (with homemade adapter cables) or using a simple hole in the chamber with a ferrite loaded cable. The last option may provide the most flexibility. Another thought crossed my mind. If you did use a filtered RJ45, you may find that its filtering will cause trouble with higher speed (100Mb/s) ethernet traffic. I guess that I'd try one first before mounting it in the chamber wall. Ho, Ho, Ho --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
power supply to GOST 30429-96
Dear Fellow EMC workers, I am trying to get a SMPS to pass this GOST standard and am having a devil of a time getting it done. After 3 days of mitigation testing at our local lab we are still out at the low frequency range 10-60kHz and at 15-50MHz. We pass the Class A limits for CISPR 22 but these GOST limits are far more stringent. The power supply is convection cooled in a IP66 box that is powering a repeater. We have been able to determine that the noise is being generated by the power supply and thus far we are not able to suppress all the low frequency and high frequency conducted noise. I have copied the limit requirements below for your review. Has anyone run into this standard before? Is there something we may be overlooking? We are not using a custom supply, this is an off the shelf supply that we are packaging into a IP66 box. The usual fixes didn't seem to work, X and/or Y caps, ferrite beads, inductor. These were applied liberally during the past 3 days. The requirements for EMC of radio equipment in Russia (as well as in several other CIS countries) are set by the standard GOST 30429-96 (Electromagnetic Compatibility of technical equipment. Man-made noise from equipment and apparatus used t6ogether with service receiver systems of civil application. Limits and test methods), according to this standard the following measurement must be done. 1. Conducted Emissions Frequency range Limits, dB(uV) 0.009 MHz - 0.15 MHz U = 90 - 28.9lg(f/0,01) (Quasi-peak) 0.15 MHz - 0.5 MHz U = 66 - 22.7lg(f/0,15) (Quasi-peak) 0.5 MHz - 6 MHz U = 54 - 12.97lg(f/0,5) (Quasi-peak) 6 MHz - 30 MHzU = 40 (Quasi-peak) 30 MHz - 100 MHzU = 48 (Quasi-peak) 40 (Average) This test is done looking at the emissions from the 220 V power cables, using a LISN 2. Radiated Emissions Frequency range Limits, dB(uV/m) 0.01 MHz - 0.15 MHzE = 60 - 20.4lg(f/0.01) 0.15 MHz - 30 MHz E = 37 - 7.39lg(f/0.15) 30 MHz - 100 MHzE = 36 - 21.0lg(f/0.30) 100 MHz - 1000 MHzE = 25 + 20.0lg(f/100) According to GOST 30429-96 this test is done at 3 meters in frequency range 0.01MHz - 30 MHz and at 1 meter in frequency range 30 MHz - 1000 MHz in the screen room. Any help will be eagerly accepted. Best regards and happy holidays, Lou Guerin Agency Approvals Manager Littlefeet, Inc. lgue...@littlefeet-inc.com mailto:lgue...@littlefeet-inc.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: High Frequency Pre-amp
Bob, the Schaffner preamp goes to 3 GHz I believe, Derek. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: Fw: working voltage measurement
Hi Xing Weibing: One of the problems of making oscilloscope measurements within switching-mode power supply circuits is that the common side of the oscilloscope *MAY* change the waveform. There are two ways to minimize the effect of the common side of the scope from affecting the waveform: 1) If you are using a mains-operated scope, supply the SMPS from an isolating transformer where both supply conductors are isolated from ground. In this way, you can connect the scope common lead to any point in the SMPS with minimum effect on the waveform. 2) Use a battery-operated scope such as the Fluke Scopemeter. You can connect the scope common to any point in the SMPS with minimum effect on the wavefrom When a scope measures the RMS value of a waveform, it does so over the time displayed on the screen. If the time base is changed, then the RMS value *WILL* change because the displayed waveform is changed. Likewise, when the trigger level is changed, the display changes the starting point for RMS calculation, and the RMS value may change if the waveform is not repetitive for the duration of the time base. An accurate RMS value is obtained when the scope measures complete, full cycles of the waveform. If the number of cycles is not full, then the RMS value is the value for the number of full cycles plus the partial cycle, and will not represent the RMS value of interest. To get a useful RMS value of a complex waveform, use a very long time base, such as 0.1 second/division or longer. You can verify that this is a useful RMS value if the RMS value does not change significantly with trigger level or time base setting. If you are making measurements of primary voltages with respect to secondary circuits, then you must ground the secondary circuits, and operate the SMPS from a grounded- neutral supply. (If you use an isolating transformer for primary-secondary voltage measurements, there is no reference for the primary circuit, and all measured voltages are incorrect.) Good luck! Best wishes for the holiday season, Rich Hi Group I have a question regarding working voltage measurement of IEC 60950 we have a E.U.T.(switching power supply) I want to clarify the measurement of working voltage 1. Using an oscilloscope having an adequate bandwith and using a high impedance probe (100Mohm), and adequate integration time to measure working voltage. The load on the secondary circuits is to be varied in order to find highest voltage across the insulation. Floating secondary outputs (capacitively connected to earth) are earthed. 2. don't make connection between primary winding and secondary winding. 3. we will get a stable waveform on the oscilloscope. working voltage we measure are as follows: The waveform we get by the above method is a kind of waveform modulated by high-frequency switching waveform. MEASURED voltage: 246V(rms),576V(peak) When we change trigger level and time base to obtain stable switching waveform, we get different rms voltage with different trigger level. the highest rms voltage we get is 380V. My question 1. the above steps are correct or not? 2. For switching power supply, what waveform of working voltage is correct for primary and secondary How to obtain? 3. Which one(246V, 380V) is correct for working voltage measurement? or other methods? Thank you for any comments in advance Best Regards Xing weibing 2001-12-17 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: EMI guard bands
John Woodgate wrote: I would be suspicious of that; it is a 'near-field' scenario, which means that the emission field strengths are complex and impossible to calculate. The Class B limits are related to a 10 m separation of source and potential victim, and that implies far-field conditions for emissions above about 5 MHz. That's true, but weren't the early measurements for Class B done at 3 meters? - 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: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Official IEC FAQ for IEC 61508 (Functional safety of E/E/PE SRS)
I thought some PSTC subscribers (especially any involved in safety systems that depend at least in part on software or electronics) might be interested in this. The IEC has recently (Dec 2001?) posted an FAQ for IEC 61508, Functional safety of electrical/electronic/programmable electronic safety-related systems. http://www.iec.ch/61508/ It is not a substitute for the standard (which has seven parts, total about 500 pages). The FAQ is only about 18 pages. Much better to browse the hyperlinked FAQ, but I have pasted a few quotes below anyway. best regards, glyn PS: Season's Greetings to you all. Glyn R. Garside TUV Rheinland of North America, Inc. (Chicago Office) 1945 Techny Rd, Unit 4, NORTHBROOK, IL 60062-5357, USA http://www.us.tuv.com TEL +1-847-562-9888 ext 25 Nationally Recognized Test Laboratory -- ANSI, UL -- CSA, SEMI EU Notified Competent Body -- CE, EN -- ISO, IEC, CB-scheme Safety, EMC, Machinery, Pressure, Quality, Ergonomics, Automotive, Medical, Telecom. - [Extracts from http://www.iec.ch/61508/ ] This document answers some Frequently Asked Questions (FAQs) about the international standard IEC 61508, Functional safety of electrical/electronic/programmable electronic safety-related systems. It has been compiled by SC65A/WG14 in collaboration with SC65A/MT12 and SC65A/MT13, the international committees responsible for the maintainance of IEC 61508. The answers to the questions are not intended to provide a definitive technical answer but rather to inform the new user to the standard. IEC 61508 sets out a generic approach for all safety lifecycle activities for systems comprised of electrical and/or electronic and/or programmable electronic (E/E/PE) components that are used to perform safety functions. The seven part standard considers all relevant overall, E/E/PE system and software safety lifecycle phases (for example, from initial concept, through design, implementation, operation and maintenance to decommissioning). This unified approach has been adopted in order that a rational and consistent technical policy be developed for all electrically-based safety-related systems. A1) What systems does IEC 61508 cover? IEC 61508 applies to safety-related systems when one or more of such systems incorporate electrical and/or electronic and/or programmable electronic (E/E/PE) devices. It covers possible hazards caused by failure of the safety functions to be performed by the E/E/PE safety-related systems, as distinct from hazards arising from the E/E/PE equipment itself (for example electric shock etc). It is generically based and applicable to all E/E/PE safety-related systems irrespective of the application. It is recognized that the consequences of failure could also have serious economic implications and in such cases the standard could be used to specify any E/E/PE safety-related system used for the protection of equipment or product. The scope of IEC 61508-1 gives more details. B4) What is a basic safety publication? Parts 1, 2, 3 and 4 of IEC 61508 are designated as IEC basic safety publications. This means that IEC Technical Committees will have to use these parts in the preparation of each of their own sector standards that has E/E/PE safety-related systems within its scope. IEC 61508 will therefore have far reaching implications across all IEC application sectors. Note that basic safety publication status does not apply in the context of low complexity E/E/PE safety-related systems or where the required safety integrity of the E/E/PE system is less than the lowest safety integrity level in IEC 61508. D3) What is a low complexity E/E/PE safety-related system? This is defined in 3.4.4 of IEC 61508-4 as an E/E/PE safety-related system, in which the failure modes of each individual component are well defined and the behaviour of the system under fault conditions can be completely determined. An example is a system comprising one or more limit switches, operating one or more contactors to de-energize an electric motor, possibly via interposing electromechanical relays. SOURCE: This material may be freely reproduced, except for advertising, endorsement or commercial purposes. The International Electrotechnical Commission (IEC) must be acknowledged as the source. All such extracts are copyright of IEC, Geneva, Switzerland. All rights reserved. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to:
RE: RJ45 filtered connector
Ron, Yours is an interesting suggestion to use filtered DB25 connectors on the chamber connector panel, and RJ45-DB25 adapters inside and out. My only comment would be to be careful of DB25 filters with any significant capacitance from signal to shield. When used with RJ45 adapters, these capacitors add in series to become differential filters (signal-cap-shield-cap-signal) and seriously attenuate 10/100BaseT signal pairs to the point where ethernet won't work. I think I'll try your suggestion with series L elements in the DB25 filter. Happy holidays, Dan Subject: RE: RJ45 filtered connector To: emc-p...@ieee.org Cc: rhe...@vicon-cctv.com From: Ron Pickard rpick...@hypercom.com Date: Thu, 20 Dec 2001 15:39:39 -0700 X-MIMETrack: Serialize by Router on AZPHXN01/Hypercom/US(Release 5.0.5 |September 22, 2000) at 12/20/2001 03:39:40 PM MIME-Version: 1.0 X-Resent-To: Multiple Recipients emc-p...@majordomo.ieee.org X-Listname: emc-pstc X-Info: Help requests to emc-pstc-requ...@majordomo.ieee.org X-Info: [Un]Subscribe requests to majord...@majordomo.ieee.org X-Moderator-Address: emc-pstc-appro...@majordomo.ieee.org Hi Reg, Trying to find a bulkhead RJ45 (shielded filtered) connector for an EMC chamber may prove to be an impossible task as, IMHO, this type of connector might be fairly fragile and hard to install for such use. To that end, I will offer some suggestions: 1. Talk to chamber manufacturers. I am quite sure that they would know about such a connector if one exists. 2. A bulkhead mounted DB25 connector might work. These can come filtered, however, the filtering involved should not impact the communication speeds you will be working with. To connect to standard ethernet cables, use 2x(DB25-RJ45) adapters (1 inside 1 outside). The whole thing would be connected as Outside Cable - Adapter - Bulkhead DB Connector - Adapter - Inside Cable. These adapters are quite common and shouldn't need to be filtered as the DB connectors would do that and if extra filtering is needed, a simple clip-on ferrite might be all that's needed (the ferrite might even be put inside the adapter backshell). And, the DB25 connector might be used for other interfaces during testing, as well. 3. You shouldn't need any connector if your EMC chamber has a ventilation opening. Just fit a cable thru the opening and put enough ferrite around the cable (inside and outside) to suppress any common mode interference. These suggestions are intended to get all those neurons firing to think of some connector alternatives to the one you're seeking. I hope this helps. Comments anyone? Bring on the flames. :-) Best regards, Ron Pickard rpick...@hypercom.com JK15@exchange.SanDiego CA.NCR.comTo: rhe...@vicon-cctv.com, emc-p...@majordomo.ieee.org Sent by: cc: owner-emc-pstc@majordomo.iSubject: RE: RJ45 filtered connector eee.org 12/20/01 12:34 PM Please respond to JK15 Reg, Look at Regal Electronics at http://www.regalusa.com. They have board mounted RJ-45 that have gasketing appropriate for a panel. Jim Jim Knighten, Ph.D. Teradata, a Division of NCRhttp://www.ncr.com 17095 Via Del Campo San Diego, CA 92127 USA Tel: 858-485-2537 Fax: 858-485-3788 jim.knigh...@ncr.com -Original Message- From: Reginald Henry [mailto:rhe...@vicon-cctv.com] Sent: Thursday, December 20, 2001 10:51 AM To:emc-p...@majordomo.ieee.org Subject:RE:RJ45 filtered connector To All, Can anyone out there tell me where I would be able to purchase a fully
High Frequency Pre-amp
This question may have recently posted but I'm not able to search the archives so I'll ask again. We have an immediate need for a pre-amp above 1000 MHz. Would you be so kind as to let me know what brands/models and frequency range you are using. Any pro/con insights would be welcome as well. Please contact me on or off-line. Thanks, Bob Heller 3M Product Safety, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: RJ45 filtered connector
Happy Holidays Reginald, Corcom also makes flanged/filtered RJ45 (or 8 pin modular, if you prefer) jacks. I have seen many manufacturers that filter these jacks (Amphenol, Amp, Corcom, possibly LZR...). Most of them have already been mentioned. Problem is, I'm not sure what you mean by a bulkhead mount. If you are looking for a connector that has a built in mounting mechanism that you can just fasten to the wall...I think that you'll be disappointed. The connectors that I've seen are designed for PCB mounting. Of course, I haven't seen everything and I hope you find what you're looking for. If not, and if you really are determined to have a bulkhead RJ45; I would suggest rigging up your own bulkhead connector using one of the flanged and filtered models from Corcom or Regal. If this won't work, I like the suggestion made in another posting to use either a filtered Dsub (with homemade adapter cables) or using a simple hole in the chamber with a ferrite loaded cable. The last option may provide the most flexibility. Another thought crossed my mind. If you did use a filtered RJ45, you may find that its filtering will cause trouble with higher speed (100Mb/s) ethernet traffic. I guess that I'd try one first before mounting it in the chamber wall. Ho, Ho, Ho For those in the Christmas spirit... How about a version of jingle bells... If not, you can delete now. Dashing to the lab In my Chevrolet Gonna take a stab At the CE mark today Find those noisy leaks Make them good and tight Hope I get it done and skip that double shift tonight Oh, EMI, RFI, keeps us all employed Keep 'em quiet and keep 'em safe so products get enjoyed Oh, copper tape, reynolds wrap, all tools of the trade. Here's one guy's sarcastic wish for a happy holiday Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: Knighten, Jim L [SMTP:jk100...@exchange.sandiegoca.ncr.com] Sent: Thursday, December 20, 2001 2:34 PM To: Reginald Henry; emc-p...@majordomo.ieee.org Subject: RE: RJ45 filtered connector Reg, Look at Regal Electronics at http://www.regalusa.com. They have board mounted RJ-45 that have gasketing appropriate for a panel. Jim Jim Knighten, Ph.D. Teradata, a Division of NCR http://www.ncr.com 17095 Via Del Campo San Diego, CA 92127 USA Tel: 858-485-2537 Fax: 858-485-3788 jim.knigh...@ncr.com -Original Message- From: Reginald Henry [mailto:rhe...@vicon-cctv.com] Sent: Thursday, December 20, 2001 10:51 AM To: emc-p...@majordomo.ieee.org Subject: RE:RJ45 filtered connector To All, Can anyone out there tell me where I would be able to purchase a fully shielded and filter RJ45 connector that is Bulkhead mountable. The RJ45 must be able to handle data rates from 10Base T to 100Base T I will be performing CE testing in the chamber so it must be bulkhead mountable ! Thanks and Happy Holidays to YOU ALL ! Reg --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at:
Re: EMI guard bands
The CE limits were designed entirely empirically but the RE limits were based on EIA TV standards that require a specified signal quality for a given rf input level. The RE limits were simply set X dB below that EIA specified level. My recollection is that the rf level specified would be a long way from a broadcast tower. -- From: John Woodgate j...@jmwa.demon.co.uk To: emc-p...@majordomo.ieee.org Subject: Re: EMI guard bands Date: Thu, Dec 20, 2001, 1:52 PM I read in !emc-pstc that Doug McKean dmck...@auspex.com wrote (in 006801c18988$24b4a2a0$3e3e3...@corp.auspex.com) about 'EMI guard bands', on Thu, 20 Dec 2001: Anywho, the answer I got back from him was that the limits were empirically derived in reference to interfering with television signals. So, the worst case (which turned out to be Class B) was a tv back to back across a wall from another device in an apartment complex. I would be suspicious of that; it is a 'near-field' scenario, which means that the emission field strengths are complex and impossible to calculate. The Class B limits are related to a 10 m separation of source and potential victim, and that implies far-field conditions for emissions above about 5 MHz. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Well Wishes
Hey folks, Happy Holidays for those celebrating! Kaz Gawrzyjal Dell Computer Corp --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: RJ45 filtered connector
Acutally, the term RJ is used by the FCC for designating connectors that are part of the registration (now approval) process. So why would you want to call a ethernet connector by a designation used by the telephone industry? I am not going to police the use of the term, but I wanted to put that information out to everyone. Regards, John Shinn -Original Message- From: Bill Owsley [mailto:ows...@cisco.com] Sent: Thursday, December 20, 2001 2:32 PM To: John Shinn; 'Reginald Henry'; emc-p...@majordomo.ieee.org Subject: RE: RJ45 filtered connector so if we called it an RJ-48C, would that be better ?? At 04:56 PM 12/20/2001 , John Shinn wrote: Although it may suprise some, and I may get flak, but an RJ45 connector is an specific configuration used exclusively for a programmable data connection. It has a specific wiring configuration. The RJ stands for Registered Jack. This is an FCC designation of that specific configuration. There is nothing against using an 8-pin modular plug/jack for 10Base-Tor 100Base-T, or even microphone inputs to my Ham radio, but do not call it a RJ45. Now, yes, there are several vendors that produce shielded and filtered 8-pin modular jacks. I remember using them and working with several vendors a few years ago, but I would suggest you look at the website or catalogs of the major connector suppliers. John Shinn, P.E. Manager, Lab. Operations. Sanmina-SCI -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Reginald Henry Sent: Thursday, December 20, 2001 10:51 AM To: emc-p...@majordomo.ieee.org Subject: RE:RJ45 filtered connector To All, Can anyone out there tell me where I would be able to purchase a fully shielded and filter RJ45 connector that is Bulkhead mountable. The RJ45 must be able to handle data rates from 10Base T to 100Base T I will be performing CE testing in the chamber so it must be bulkhead mountable ! Thanks and Happy Holidays to YOU ALL ! Reg --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. Bill Owsley, ows...@cisco.com 919) 392-8341 Compliance Engineer Cisco Systems 7025 Kit Creek Road POB 14987 RTP. NC. 27709
Re: EMI guard bands
I read in !emc-pstc that Doug McKean dmck...@auspex.com wrote (in 006801c18988$24b4a2a0$3e3e3...@corp.auspex.com) about 'EMI guard bands', on Thu, 20 Dec 2001: Anywho, the answer I got back from him was that the limits were empirically derived in reference to interfering with television signals. So, the worst case (which turned out to be Class B) was a tv back to back across a wall from another device in an apartment complex. I would be suspicious of that; it is a 'near-field' scenario, which means that the emission field strengths are complex and impossible to calculate. The Class B limits are related to a 10 m separation of source and potential victim, and that implies far-field conditions for emissions above about 5 MHz. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
