In message <[email protected]>, dated Thu, 30 Sep 2010, "ce-test, qualified testing bv - Gert Gremmen" <[email protected]> writes:
>No John, while what you state is correct, >the coupling from CM currents out of the ground >via the center tap of the transformer is one common way of creating >problems. Now I'm completely confused. Earlier in this thread, you wrote: Most of the time the problem is that the ground point center-tap of the Ethernet transformer is insufficiently grounded. Now you seem to be saying that the equipment 'ground' can be a source of CM energy, and I agree it can be. Therefore, it would be better NOT to ground the centre-tap. >And much more likely then balancing problems. Balancing problems will >immediately be detected by poor transfer rates and errors. CM current >will go unnoticed. I don't think so. The balance has to be a long way off before it noticeably affects the signal transfer, but only a little way off to significantly increase emission levels. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK If at first you don't succeed, delegate. But I support unbloated email http://www.asciiribbon.org/ - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
