Doug, Please see below... In a message dated 12/22/2004 14:58:38 GMT Standard Time, [email protected] writes:
As to functional insulation requirements, one could apply 5.3.4 c) 1), assuming that the PWB is V-1 or better. Agreed, hence my earlier comment "if they don't, it would be necessary to short them out - which in this application would be a real no-no". Of course per IEC/EN60950-1 you would just apply a dead short-circuit but we all know that test doesn't represent all failure modes and in real life the fault will have some resistance. If, as a manufacture, you choose to apply some engineering thought rather than just blindly applying the standard then you may find a load condition that causes overheating in the circuit board or the interconnect cabling (if any). Use a fuse and that problem doesn't occur (and no I'm not saying that electronic circuit breakers or trips don't have their place, just that the humble fuse still has some useful life left in it!). Thanks for stimulating the old brain cells! It's a pleasure! Merry Christmas or seasons greetings, as applicable to you. Richard Hughes ---------------------------------------------------------------- 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: 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
