Thanks for the quick response. Please let me explore this further. I have used the "special case" as the general case where the EUT has many signal lines in which it would be too costly and impractical to have a CDN on each line. The special case allows the test engineer the flexibility of disregarding the multiple impedances by way of the method described in the body of the document and amplified in Annex A. I will admit I somehow missed the point about the lower impedance requirement of the AE. In the case where a CDN is installed on each line from the EUT, how are the signal line shields handled at the EUT - left unterminated, terminated to ground, or terminated to the metallic case? EN61000-6-2 is the generic immunity standard we use. It states the functional earth port of the EUT will be tested using this basic standard. If the earth is to be lifted, how is this possible?
I was not a member of this community in 1997 thus do not have a copy of the symposium record. Is it available on the IEEE site? Thanks again for your quick response. Dan Kinney > -----Original Message----- > From: Ken Javor [SMTP:[email protected]] > Sent: Friday, February 14, 2003 4:41 PM > To: Dan Kinney (A); Oliver Betz; [email protected] > Subject: Re: Grounding of EUT in EN61000-4-6 conducted immunity test > > I was working off IEC 1000-4-6 (1996), Figures 2 and 5b, which cover > direct > injection and show the EUT isolated above ground. Figure 6 shows clamp > injection and EUT isolation above ground. What you are referencing is a > special case in the annex when the cm 150 Ohm impedance cannot be met. > The > theory is, I believe, as I stated before. Incidentally clamp injection is > fundamentally different than CDN injection. CDN injects line-to-ground, > and > clamp injects in series with the cable. The standard specifically says > that > when using a clamp installed between EUT and AE, the AE must be an equal > or > lower impedance than the EUT. This is opposite of what you want with a > CDN. > My paper covers that issue in detail. It appeared in the 1997 IEEE EMC > Symposium record, page 479. > > Ken Javor > 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: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
