Brian, I believe the root cause to be the construction of the surge coupler/decoupler (specifically the decoupler side). The standard shows simplified schematics of the decoupler, with caps between all the lines, and I assume that the caps, along with some weak inductors, are the culprits. Of course, when I asked for a schematic of the surge coupler, they refused to supply them. :-( I forgot to mention that the voltages I measured were without any device connected to the surge coupler. So, with nothing connected, when I surge 2kv >from line-PE, I see 1.6kv line-neutral. Bob Richards, NCT.
Brian O'Connell <oconne...@tamuracorp.com> wrote: As I have not seen this extreme (for a correctly constructed UUT) I would have to assume that none of my units were "completely normal". Perhaps the common-mode input chokes do not have well-matched windings ? I am very curious about this effect; if you can, pls advise on the root cause. luck, Brian From: emc-p...@ieee.org [mailto:emc-p...@ieee.org]On Behalf Of Bob Richards Sent: Tuesday, June 05, 2007 11:35 AM To: ieee Subject: Surge coupler anomaly In surge testing a product to 61000-4-5, we had a failure that could not be explained. So, we investigated and found that during a 2kv surge line-PE, we were seeing about 1.6kv line-neutral. The spec only requires 1kv line-neutral, and 2kv line-PE and neutral-PE. But when we surge line-PE we get much higher than the required 1kv line-neutral. I emailed the manufacturer of the surge equipment, and was told this is "completely normal". Has anyone else observed this kind of behaviour from you surge equipment? Thanks in advance, Bob Richards, NCT. - 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 emc-p...@ieee.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 emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc - ---------------------------------------------------------------- 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 emc-p...@ieee.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 emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________
