Eric, I am not sure about your question. To pass the Hygroscopic dust test in the past, I have not had issues if the following two items are addressed:
1. Air is properly filtered. 2. The maximum voltage gradient between pins does not exceed 12V/mil. (mil = thousandth of an inch) That does not mean that a higher voltage gradient will necessarily fail just that this level is low risk. The level was arrived at experimentally - not with any simulations. I have only had experience with regular FR-4 (& there high-speed variants) and with ceramic hybrids but I cannot see that any other laminates will have issues. Cheers, Marko From: [email protected] [mailto:[email protected]] On Behalf Of Meunier, Eric Sent: Wednesday, December 07, 2005 1:34 PM To: ieee pstc list Subject: Design for GR-63 Hygroscopic Test Hi, Would someone know what value of surface resistivity we should assume for PCB design and simulation purposes in order to pass the NEBS GR-63-CORE Hygroscopic Dust Test of Section 5.5.3 ? Thanks, Eric =================================== Eric Meunier Designer EMC/Environmental E-mail: [email protected] Kontron Canada Inc. 616, rue Cure-Boivin Boisbriand, Quebec Canada, J7G 2A7 Tel: 1-450-437-4661 ext. 2419 Fax: 1-450-437-8053 - 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/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: Jim Bacher: [email protected] David Heald: [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/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: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
