Hi Alex We always use what you mentioned “discharge before next zap” method. I do not see that there is requirement in the standard to 'ground' ungrounded equipment for the sake of ESD testing. Best Regards, Kyaw
From: [email protected] mailto:[email protected]] On Behalf Of Alex McNeil Sent: Friday, December 03, 2004 9:26 PM To: [email protected] Subject: EN61000-4-2 for "ungrounded products" Hi Guys, I have recently been using the “test method for ungrounded equipment” for tabletop equipment. Specifically the method where you attach a metallic accessible part of the ungrounded EUT to the HCP via a cable with bleeder resistors (470K X 2). I am finding this method much more severe (in reference to test results) than the previous method of applying an ESD zap to this metallic part i.e. discharging before the next zap. The result is that I have products that previously passed ESD using the “discharge before next zap” method and failing if tested using the “...via cable to the HCP” method. What results do I take? Is it best to use the “discharge before next zap” or “allow time to discharge i.e. 1Zap/10secs” or “via cable to HCP” method? And can I instruct my Test House what method to use? I would prefver to use whatever method is more “real life”. Also, Should the HCP still be connected to the ground plane via the 940K when using the via cable to HCP method i.e. 1880K total? Your help would be much appreciated as I am now in “Panic Mode”! Thank You and Best regards Alex ________________________________________________________________________ This email has been scanned for all known viruses and appropriate content by the Messagelabs mail service. ---------------------------------------------------------------- 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: Ron Pickard: [email protected] Scott Douglas [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 ---------------------------------------------------------------- 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: Ron Pickard: [email protected] Scott Douglas [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
