I read in !emc-pstc that am...@westin-emission.no wrote (in <LFENJLPMMJB mhpeibnilieiocdaa.am...@westin-emission.no>) about 'Surge test on a loop', on Wed, 20 Mar 2002: >Assume a fire alarm detection system. 10 smoke detectors are connected in >series on a loop and both ends of the loop is connected to the fire alarm >panel. Shielded cable is used and the shield is connected through the whole >loop. > >So, how do we carry out the surge test on the loop? The alarm panel and the >detectors are all EUTs. > >As far as I understand IEC61000-4-5:1995 chapter 7.5, I will insert an extra >20 meter shielded cable between each detectors and then I will drive the >surge pulse onto the shield in order to test one of the detectors. Then I >move the extra 20m cable to the next detector and surge test it. > >If this is correct, why can't we just put the surge pulse onto the shielded >loop and assume that the whole loop was tested at once?
You haven't said which product EMC standard you are applying. This matter should have been made clear in that standard. If it isn't, you should press for an amendment to clarify it. -- 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: 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...@mediaone.net 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"