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. And much more likely then balancing problems. Balancing problems will immediately be detected by poor transfer rates and errors. CM current will go unnoticed.
Regards, Ing. Gert Gremmen [email protected] www.cetest.nl Before printing, think about the environment. -----Oorspronkelijk bericht----- Van: [email protected] [mailto:[email protected]] Namens John Woodgate Verzonden: Wednesday, September 29, 2010 11:05 PM Aan: [email protected] Onderwerp: Re: [PSES] EMI issue with Ethernet In message <[email protected]>, dated Wed, 29 Sep 2010, "Oglesbee, Robert A" <[email protected]> writes: >How the transformer is wound also makes a big difference. ... because it affects the values of the impedances from each end of the secondary winding to any reference point. This effect MAY be minimised by the grounding of the centre-tap of the secondary winding - if it REALLY is exactly in the centre. Otherwise, it may make things worse. -- 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]> - ---------------------------------------------------------------- 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]>
