In message <[email protected]>, dated Tue, 6 Feb 2007, David Cuthbert <[email protected]> writes
>I'm avocating designing the trace for continuous fault current. For >example, for 30 amps through 1 oz copper the trace width can be 2.5 cm >for a 50 deg C rise. These days, 2.5 cm is the longest dimension of the whole board. Would not continuous 30 A damage other things, quite apart from the track? And how could it occur? Failure of the protective device is usually considered a negligible probability. I have teased safety standards committees by asking if fitting the wrong fuse is 'foreseeable misuse'....? > >For transient conditions (such as until a fuse opens) an adibiatic Your spell-checker needs a 10 000 character service.(;-) I wouldn't mention it, but somebody might try to look that word up. Try 'adiabatic'. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk There are benefits from being irrational - just ask the square root of 2. John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - 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 email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________
