http://www.ieee-pses.org/symposium http://www.emc2004.org/
It's interesting to note that 60664-1 in clause 3.3.1 says that, "It is not appropriate to specify the minimum thickness of solid insulation to achieve long-term electric withstand capability". However, some product-specific standards do specify a minimum thickness, without investigation. Ralph McDiarmid, AScT Compliance Engineering Group Xantrex Technology Inc. > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Rich Nute > Sent: August 11, 2004 10:51 AM > To: [email protected] > Cc: [email protected] > Subject: Re: solid insulation vs coating > > > http://www.ieee-pses.org/symposium > http://www.emc2004.org/ > -------------------------------------------------- > > Hi John: > > > > Could it be that the authors assumed that the layers > could separate, > > locally and perhaps minutely, since there is no (?) > practicable way > > (maybe ultrasound?) to determine for sure that they > don't. If they do, > > the atmosphere in the gap may contain all sorts of stuff > that could > > impair the surface resistivity of the layers, and even promote > > tracking. > > > > Just conjecture: someone who knows should explain for certain. > > Your point is taken. > > IEC 60664-3 specifies peel strength testing for > coatings as well as other conditioning tests to > determine adherence. IEC 60664-3 also specifies > partial discharge testing for such constructions. > > I mentioned both cement and amalgam as a means > for a strong joint as well as an air-exclusion > joint. > > The dimensions for distance through insulation > start at 0.01 mm for 330 volts peak. Another > point is 1.2 mm at 4 kV peak. This second > point will indeed break down if there is any > air whatsoever (unless the field is exactly > homogeneous). See IEC 60664-1, Table A1. > > > Best regards, > Rich > > ------------------------------------------- > > This message is from the IEEE Product Safety Engineering > Society emc-pstc discussion list. > > IEEE PSES Main Website: http://www.ieee-pses.org/ > > To post a message send your e-mail to [email protected] > > Instructions for use of the list server: > 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] Dave Heald: [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. IEEE PSES Main Website: http://www.ieee-pses.org/ To post a message send your e-mail to [email protected] Instructions for use of the list server: 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] Dave Heald: [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
