Didn't the IEC publish a number for maximum expected impedance of the 50Hz public system in Europe? I recall something like 0.4+0.2j
Ralph McDiarmid, AScT Compliance Engineering Group Xantrex Technology Inc. From: [email protected] [mailto:[email protected]] On Behalf Of Robert A. Macy Sent: July 21, 2005 7:22 AM To: John Woodgate Cc: [email protected] Subject: Re: It's too quiet John, I'm still digesting the thread regarding variability of that test. Here, I've measured effective impedance of the lines anywhere from 0.003 to 0.3 ohms. Once made a big difference in ground leakage test a for hospital product. The US govt paid for a study finding the "expected" impedance of AC mains over the spectrum of fundamental up to 1 MHz for residential, simple industrial, and medium sized industrial. Although very thick, copy makes interesting reading. There should be some way to predict the maximum "envelope" of the harmonics given a perturbation to the impedance. Or, simply, sweep the impedance over an expected range. Variability always suggests lack of controls. After all, science is in the business of verifiable/repeatable experimentation. Forgot, EMC is not a science. :-) - Robert - PS let us know if you don't get this one. On Thu, 21 Jul 2005 07:31:27 +0100 John Woodgate <[email protected]> wrote: > I didn't receive any messages yesterday, so I wonder if there is a > transmission problem. > -- > Regards, John Woodgate, OOO - Own Opinions Only. > Deadlines are 90% of deadliness. > http://www.jmwa.demon.co.uk Also see > http://www.isce.org.uk > > > 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 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 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
