Re: Filtering 100 BaseT during immunity
snip On the other (AUX) side of the transformers conect the center taps directly to the ground panel. You don't care about high-voltage isolation in this application, so you don't need any caps. How do you cope with ground potential differences, with centre-taps grounded at each end of the cable? -- Regards, John Woodgate, OOO - Own Opinions Only. Center taps are not grounded on each end of the cable. I recommended adding transformer in-line, at the location of the feedthrough panel. Each device (DUT and AUX) has a transformer and high- voltage isolation in the front end. For RF coupled on the Ethernet line, which you want to filter out before it reaches the AUX equipment, the transformer you put in series with line effectively brings common-mode voltage on the cable to the voltage of the feedthtough panel (hopefully close to such low voltage that can not upset the AUX equipment). Additionaly, common-mode chokes in the part will further help reduce higher-frequency content that might go through due to any imbalance in the transformer center tap. Neven --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
ESD Gun
I'm currently renting a Schaffner NSG435 ESD Gun and like the features. Would anyone be able to provide me with some leads where I might be able to get a deal (used is OK) on a comparable piece of equipment to purchase? I find the continuous feature to be a necessity as well as the ability to set the pulse frequency to 0.5 Hz (2 pps) or less. Any leads would be appreciated. Any solicitation is encouraged to be done off line. Thx, Joe *** Joe Finlayson Manager, Compliance Engineering Telica, Inc. 734 Forest Street, Bldg. G, Suite 100 Marlboro, MA 01752 Tel: (508) 804-8212 Fax: (508) 480-0922 Email: jfinlay...@telica.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: Dwell time for Immunity under EN55024?
Dear Gert, Thanks for trying to answer my questions - I thought your comments are so misleading, at least I would have been fooled if I were not in the profession of regulatory compliance. I thought manufacturers have already taken too much trying to understand what are the routes to comply. Obviously - if the harmonized standards are available, simply following the standards would be sufficient to declare conformity, I believe that's why the standards are there in the first place. Why should we ask manufacturers to comply with essential requirements instead of following what standard says. TCF is only for certain conditions either when there is no harmonized standard available or the standard testing is not feasible to the EUT, etc. even though during TCF assessment, standard procedures should be followed as much as possible. If your comments were not misleading, I thought we should replace all test standards with test guidelines so that we could be exploring as much value-added essential requirements as possible and fully instilling our spirit of immunity testing. As test labs, we must be laughing as we are charging by time, and our manufacturers would never get out of debts. I would like to stop here, no more discussions on this, and you know time is money, once again we are charging you, dear manufacturers, by time Leslie I declare I am running a lab in California and partially own one lab in China. Gert Gremmen wrote:Hi Leslie, some answers: Is this called compliance testing or engineering verification?Anything that has to do with product quality (like EMI) needs to be addressed in termsof engineering. Can we do this and declare compliance? Sure you can declare compliance, as the European System is simply not targeted to complying with standards,but to complying with essential requirements. Of course you cannot declare compliance withthe standard (to the letter). Using standards is just a way to presumption of compliance. Art 10.1 EMCDIf you really DO deviate from the standard , you will needto follow the TCF route using a Competent Body to show compliance. Art 10.2 EMCD Any deviation of the standard is doomed to art 10.2 , but changing an undefined dwelltime to better meet the intention of the standard won't lead to a law suite. Several product type of standards do address the topic of dwell time btw. One never can get condamned by not following the prescriptions of the EMCD or standard, onlyby creating to much EMI or lacking susceptability (and other essential phenomenae). Gert Gremmence-test-Original Message- From: Leslie Bai [mailto:leslie_...@yahoo.com] Sent: donderdag 3 oktober 2002 21:37 To: Gert Gremmen; paul_sc...@mitel.com; emc-p...@majordomo.ieee.org Subject: RE: Dwell time for Immunity under EN55024? Gert Gremmen wrote: ... prescan with Increase frequency step size ! (watch out for resonances) Modify equipment to decrease fault response time (low pass filters ; software ) Build Specifc test features Write specific test software . I am wondering whoelse out there doing these - Is that not sufficient to demonstrate conformity by follwoing standard procedures? What specific test features, what specific test software, are they specifed in the standards? Is this called compliance testing or engineering verification? Of course you will be violating the standard; Can we do this and declare compliance? Leslie Bai NARTE Certified Engineer (EMC-002112-NE) www.siemic.com - Do you Yahoo!? New DSL Internet Access from SBC Yahoo! - Do you Yahoo!? New DSL Internet Access from SBC Yahoo!
Re: Immunity Requirements
I read in !emc-pstc that Juhasz, John (IndSys, GE Interlogix) john.juh...@ge.com wrote (in 4606624A2A8ABE41AFBA5F8306F2ECB204508A@F TWMLVEM01.e2k.ad.ge.com) about 'Immunity Requirements' on Fri, 4 Oct 2002: With specific regard to electronic equipment that falls under 'light industrial' as defined for European EMC, is immunity testing (like specs under EN 50082-1) to such products required anywhere else than Europe? Possibly not, but if you want repeat orders, it's a good idea to have a modicum of immunity. (;-) -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Indai CCE
Hi, Can anyone provide information on India CCE (Chief Controller of Explosives) requirements for industrial equipment? Regards, Paul Buchner Principal Compliance Engineer Solar Turbines Inc. 858-694-6483 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Immunity Requirements
With specific regard to electronic equipment that falls under 'light industrial' as defined for European EMC, is immunity testing (like specs under EN 50082-1) to such products required anywhere else than Europe? From what I can tell I don't believe it's required anywhere else, but I want to be sure I'm missing something. John A. Juhasz GE Interlogix Fiber Options Div. Bohemia, NY --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Re: Filtering 100 BaseT during immunity
I read in !emc-pstc that neve...@attbi.com wrote (in 20021004044539.LLY C9928.rwcrmhc52.attbi.com@rwcrwbc55) about 'Filtering 100 BaseT during immunity' on Fri, 4 Oct 2002: On the other (AUX) side of the transformers conect the center taps directly to the ground panel. You don't care about high- voltage isolation in this application, so you don't need any caps. How do you cope with ground potential differences, with centre-taps grounded at each end of the cable? -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Re: Dwell time for Immunity under EN55024?
I read in !emc-pstc that Gert Gremmen g.grem...@cetest.nl wrote (in oleokfnbajjejfkplbbmieoecdaa.g.grem...@cetest.nl) about 'Dwell time for Immunity under EN55024?' on Fri, 4 Oct 2002: Any deviation of the standard is doomed to art 10.2 , but changing an undefined dwell time to better meet the intention of the standard won't lead to a law suite. The first line is a very extreme view. According to UK sources (I am not allowed to say precisely who; no, I think that's daft, too), the standards route is OK IF the product DOES pass the standard when tested precisely to it. But the original test need NOT be precisely, or even approximately, to the standard . Several product type of standards do address the topic of dwell time btw. One never can get condamned by not following the prescriptions of the EMCD or standard, only by creating to much EMI or lacking susceptability (and other essential phenomenae). which is what GG seems to be saying here. Phenomenae! Make sure you keep all the test datae! And note down any formulaes you use in calculationses. (;-) -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: Dwell time for Immunity under EN55024?
Hi Leslie, some answers: Is this called compliance testing or engineering verification? Anything that has to do with product quality (like EMI) needs to be addressed in terms of engineering. Can we do this and declare compliance? Sure you can declare compliance, as the European System is simply not targeted to complying with standards, but to complying with essential requirements. Of course you cannot declare compliance with the standard (to the letter). Using standards is just a way to presumption of compliance. Art 10.1 EMCD If you really DO deviate from the standard , you will need to follow the TCF route using a Competent Body to show compliance. Art 10.2 EMCD Any deviation of the standard is doomed to art 10.2 , but changing an undefined dwell time to better meet the intention of the standard won't lead to a law suite. Several product type of standards do address the topic of dwell time btw. One never can get condamned by not following the prescriptions of the EMCD or standard, only by creating to much EMI or lacking susceptability (and other essential phenomenae). Gert Gremmen ce-test -Original Message- From: Leslie Bai [mailto:leslie_...@yahoo.com] Sent: donderdag 3 oktober 2002 21:37 To: Gert Gremmen; paul_sc...@mitel.com; emc-p...@majordomo.ieee.org Subject: RE: Dwell time for Immunity under EN55024? Gert Gremmen wrote: ... prescan with Increase frequency step size ! (watch out for resonances) Modify equipment to decrease fault response time (low pass filters ; software ) Build Specifc test features Write specific test software . I am wondering whoelse out there doing these - Is that not sufficient to demonstrate conformity by follwoing standard procedures? What specific test features, what specific test software, are they specifed in the standards? Is this called compliance testing or engineering verification? Of course you will be violating the standard; Can we do this and declare compliance? Leslie Bai NARTE Certified Engineer (EMC-002112-NE) www.siemic.com -- Do you Yahoo!? New DSL Internet Access from SBC Yahoo!
Re: Filtering 100 BaseT during immunity
Using fiberoptic link is best if you can do it. However even so you need another end of the twisted-pair cable connected to another 100 Mbps device. You may check that device by looping it back on itself first and performing the immunity test on it. If it passes, it is safe to asume that it will not fail as supprt equipment to another DUT. Absorption clamp is an easy to use device too. What I would recommend if you really want good decoupling of your AUX equipment is to use another set of Ethernet transformers in line with your cable. The transformers must have center taps in each pair, on both sides. I recomment GBit 1:1 transformers from BelFuse or Pulse. Insert transformers in line to each pair (used and unused), close to your AUX equipment, preferably at the chamber feedthrough panel. Place 75 Ohm resistor from each center-tap on the DUT-side to GND (chamber- wall/panel) for common-mode termination. On the other (AUX) side of the transformers conect the center taps directly to the ground panel. You don't care about high- voltage isolation in this application, so you don't need any caps. If you keep the connections from the center taps very short and low-inductance, this will be almost a bulletproff combination for protecting AUX equipment. Some other additional measures come to mind, such as shielded cable on the AUX side and extra 10-15pF (max) from each line to GND, but most likely you will never really need them. All this said, there are many products on the market that meet 10V and 10 V/m, you can verify it with a pre- test as I mentioned earlier, so I don't think you really need such a bulletproof combination. You can expect much more troubles with EFT and AUX equipment than with conducted or radiated RF. Good luck, Neven I want to provide isolation for auxillary equipment while performing radiated/conducted immunity testing on 100BT LAN. Tests are performed in a shielded room, and a bulkhead is used. Right now, cables pass right through the bulkhead (with, of course, split core ferrites of varying materials clamped to the cables on either side of the bulkhead). But this is not good enough. Does anyone have an effective means of keeping the RF energy where it belongs (behind the bulkhead) ? By the way, this is low level testing, no more than 10V/m and 10 Vrms. I have an option of using a fiber link (modem) through the bulkhead, however, I am not sure if this equipment will be susceptible, and no samples are available for test. Thanks in advance. Paul --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
pwb coupling to surroundings (continued)
Hi All, I have posted at http://emcesd.com the latest Technical Tidbit (picture link at bottom of page). In April and May, the Technical Tidbit articles discussed the coupling between a circuit board and a nearby metal plane. This month, Printed Wiring Board Coupling to a Nearby Metal Plane, Part 3: System Measurements carries the discussion of board coupling to nearby objects further with measurements on a board in a system enclosure. Results are dramatic and show that a circuit board is strongly affected by nearby metal structures. Data and pictures for the article were contributed by Neven Pischl of Broadcom. If you have a topic you would like to see covered in a Technical Tidbit that fits with the general topics of the website, let me know. Doug -- --- ___ _ Doug Smith \ / ) P.O. Box 1457 = Los Gatos, CA 95031-1457 _ / \ / \ _ TEL/FAX: 408-356-4186/358-3799 / /\ \ ] / /\ \ Mobile: 408-858-4528 | q-( ) | o |Email: d...@dsmith.org \ _ /]\ _ / Website: http://www.dsmith.org --- --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
