Not a legalese answer but a technical consideration. RE are measured only above 30 MHz due to measurement accuracy concerns at lower frequencies. The CE limit, in addition to preserving power quality in radio frequency bands, also limits RE from long power lines. So there is a good technical reason for imposing the same CE limits on your dc power distribution. If you wanted an algorithm, you could say that you should control CE for the purpose of controlling RE when the power line is a tenth wavelength or longer. This should effectively remove concern at switching frequencies. Also, assuming you are routing feeder and return together, you can limit the control to common mode emissions.
---------- >From: "Terry Meck" <[email protected]> >To: <[email protected]> >Subject: EN 55022 Conducted emissions DC >Date: Tue, May 15, 2001, 3:06 PM > > > Hello all, > > Is there any new requirement on doing conducted emissions testing on > distributed DC inside a building. > RE: EN 55022:1998 > The DC comes from an AC - DC supply (compliant). > Would there be a cable length above which the conducted test must be done? > I know some immunity tests are required depending in length is this also > true of conducted emissions? > > This has no relationship to Telecom or wires leaving a building. > > Terry J. Meck > Accu-Sort Systems > > > ------------------------------------------- > 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: > [email protected] > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Michael Garretson: [email protected] > Dave Heald [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.rcic.com/ click on "Virtual Conference Hall," > ------------------------------------------- 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: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: [email protected] Dave Heald [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.rcic.com/ click on "Virtual Conference Hall,"
