<snip> > >On the other (AUX) side of the transformers conect the center taps directly to the ground panel. You don't care about high-voltage isolation in this application, so you don't need any caps. > > How do you cope with ground potential differences, with centre-taps > grounded at each end of the cable? > -- > Regards, John Woodgate, OOO - Own Opinions Only.
Center taps are not grounded on each end of the cable. I recommended adding transformer in-line, at the location of the feedthrough panel. Each device (DUT and AUX) has a transformer and high- voltage isolation in the front end. For RF coupled on the Ethernet line, which you want to filter out before it reaches the AUX equipment, the transformer you put in series with line effectively brings common-mode voltage on the cable to the voltage of the feedthtough panel (hopefully close to such low voltage that can not upset the AUX equipment). Additionaly, common-mode chokes in the part will further help reduce higher-frequency content that might go through due to any imbalance in the transformer center tap. Neven ------------------------------------------- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
