I read in !emc-pstc that Scott Douglas <[email protected]> wrote (in <[email protected]> ) about 'Do I need to Test for Harmonics?' on Tue, 22 Oct 2002:
> One argument says that we are not connected to the public > low-voltage distribution system, instead the ferroresonant supply > is. Therefore, since we ARE NOT "connected" we do not need to do > the harmonics test. That is most probably the case. What matters is what is emitted into the public supply. > The flip side argument says that we still have > to test harmonics because the supply does nothing but provide power > to our product and therefore we ARE "connected". That's not the point at all, I suspect. Is there any significant correlation between the harmonic current amplitudes at the output of the ferroresonant supply and those at its input? If not, there is absolutely no point in measuring those at its output, which are not those that are emitted into the public supply. > > Understand that this "system" consists of power supplies and > amplifiers, etc. from one or more than one supplier (read that more > than one manufacturer). We cannot guarantee we are the sole > provider here, in fact will most likely not be the sole provider. > Especially since we do not manufacture or sell power supplies. It isn't a 'system' in the sense of the EMC Directive unless the whole thing is supplied as a single article of commerce, i.e. one single item on the invoice. You are only concerned with your own product. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! ------------------------------------------- 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: Ron Pickard: [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://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
