Geetha Balasubramanian <[email protected]> wrote (in <[email protected]>) about 'Radiated Emission Testing', on Mon, 21 Mar 2005: > One of our products had been tested by an accredited lab at US >on May 2004 and found to be compliant with FCC, CE & VCCI. We started >mass manufacturing the product and it is being sold in the US, Europe & >Japan markets for the past 6 months. Then came a requirement for that >product in Taiwan market. Since the May 2004 testing at the US lab was >not run in a BSMI approved system it became necessary for us to retest >the same product. This time the product has been tested in an >accredited lab in Taiwan. The Taiwan lab tests are showing that the >product is not compliant to the CISPR22 and need a ferrite core in the >USB cable to make it compliant to the standards. Product tested by the >US lab & tested by he Taiwan lab are absolutely identical. > As an engineer responsibled for compliancy I am a bit confused >now. How to resolve this issue? I request you experts to guide me
EMC testing, even for compliance verification, is not an exact science, especially when one test shows result just under the limit and another shows a result just over the limit. The sample tested 10 months ago in USA is presumably not the same one as tested in Taiwan. But even if it was, quite a small difference in the layout of the test set-up can make quite a large difference to the results. In this case, you are very lucky. You can simply provide a USB cable with a ferrite, as Taiwan request. -- Regards, John Woodgate, OOO - Own Opinions Only. There are two sides to every question, except 'What is a Moebius strip?' http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/listserv/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: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
