Derek, That’s a really good question.
I’ve based my material decisions for this purpose on the resistance to moisture and compression and not on fundamental dielectric strength. The standards I have seen do not mention a dielectric requirement. -Doug From: [email protected] [mailto:[email protected]] On Behalf Of Derek Walton Sent: Monday, February 07, 2011 2:50 PM To: [email protected] Subject: ESD spacer Hi All, My turn to ask for opinions: all answers appreciated in advance. EN61000-4-2 requires an insulating mat to be placed on top of the HCP under the EUT. The thickness of this mat is specified at 0.5 mm, or, in imperial units, around 20 mils. My question is, whats the acceptable dielectric strength of this material? If I assume contact discharge to the metal case of an EUT at 8 kV, does this imply 8,000/20 = 400 v/mil? If so, that rules out a lot of " insulating" materials, especially paper ones that could absorb moisture. If not, why not? I can think of quite a few potential reasons, but I hate just speculating..... Sincerely, Derek Walton L F Reseach - ---------------------------------------------------------------- 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 <[email protected]> All emc-pstc postings are archived and searchable on the web at http://product-compliance.oc.ieee.org/ 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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher <[email protected]> David Heald <[email protected]> - ---------------------------------------------------------------- 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 <[email protected]> All emc-pstc postings are archived and searchable on the web at http://product-compliance.oc.ieee.org/ 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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher <[email protected]> David Heald <[email protected]>
