> A lab we're using has an interpretation of EFT testing that never > occurred to me. I'm interested in other people's understanding and > opinions. Please feel free to point me to the archives if this has > been discussed before. > > The generic immunity standard EN61000-6-1 calls out EFT on different > types of ports, and gives the applied test level. For signal ports > it's a 500V test using the clamp and for AC ports it's 1000V using a > CDN. If the clamp has a 6dB insertion loss, as our lab claims, then > the 500V spec in the standard results in application of 250V to the > EUT cable. Presumably the authors of the standard know that and > accounted for it. The CDN directly couples without 6dB of loss so > presumably the authors said 1000V with the intent of the EUT cable > actually seeing 1000V. > > So what do you do for an AC port that draws more current than the CDN > available is rated for? > > The lab's answer is to use the cap clamp, but because of the 6dB > insertion loss they doubled the generator setting to 2kV to obtain the > 1kV test that the standard calls for. Opinions? Comments? > > In 61000-4-4 it says that if the line current is higher than the > specified current capability of the CDN you should use a 33nF coupling > cap per figure 10, in which case the EUT would be powered directly > from the grid and the EFT generator's connection to the EUT is via the > coupling cap and appropriate grounding provisions (another question is > what that looks like). I may end up insisting that the lab use this > approach, but in the meantime I wanted to get the forum's opinion on > the cap. clamp method discussed above. > > Thanks, > > Jim Eichner, P.Eng. > Compliance Engineering Manager > Xantrex Technology Inc. > e-mail: [email protected] > web: www.xantrex.com > Any opinions expressed are those of my invisible friend. > Confidentiality Notice: This email message, including any attachments, > is for the sole use of the intended recipient(s) and may contain > confidential and privileged information. Any unauthorized review, use, > disclosure or distribution is prohibited. If you are not the intended > recipient, please contact the sender by reply e-mail and destroy all > copies of the original message. >
This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/listserv/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
