You should be using a different test lab. We have never had that much of a variation on the same EUT. I attribute that to using a true EMI receiver, which has much better amplitude accuracy then a spectrum analyzer. But that is a whole different discussion. I have seen products leave the lab and come back and have the same profile within 1 dB or less. Larry Stillings Compliance Worldwide, Inc.
________________________________ From: Amund Westin [mailto:am...@westin-emission.no] Sent: Friday, October 29, 2010 4:34 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: SV: [PSES] Different Radiated Emissions results at different labs Quite often I see 4-5 dB variation on the same EUT and on the same lab. Day 1: Make measurement. Take down the test setup. Day 2: New measurement. Same EUT. Tries to recapitulate the test setup with same EUT position on the table and cables. This is a challenge .... J #Amund Fra: Charlie Blackham [mailto:emcp...@sulisconsultants.com] Sendt: 29. oktober 2010 09:04 Til: EMC-PSTC@LISTSERV.IEEE.ORG Emne: [PSES] Different Radiated Emissions results at different labs Group Testing a product to CISPR11 class B and seeing quite a difference in results below 1 GHz when tested at two different labs. I don't wish to discuss why this is being done, but would be very grateful for any Quantitative data people have on differences between different OATS or between OATS and semi-anechoic or anechoic chambers. (The EUT is a small box with a single 2-core 24V dc/signal cable) Regards Charlie Charlie Blackham Sulis Consultants Ltd Tel: +44 (0)7946 624317 Web: www.sulisconsultants.com <http://www.sulisconsultants.com/> Registered in England and Wales, number 05466247 - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <emcp...@radiusnorth.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher <j.bac...@ieee.org> David Heald <dhe...@gmail.com> - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <emcp...@radiusnorth.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher <j.bac...@ieee.org> David Heald <dhe...@gmail.com> - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <emcp...@radiusnorth.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher <j.bac...@ieee.org> David Heald <dhe...@gmail.com>
