In message <[email protected]>, dated Mon, 21 Apr 2008, "Kunde, Brian" <[email protected]> writes:
>I'm mostly familiar with linier and switch mode power supplies that >includes an isolation transformer for user safety. I assume with the >above power supply using an auto transformer, that this would only be >allowed if the user is separated from any circuit by double or >reinforced insulation. Even though it is low voltage DC, it is not >isolated from the mains so if the user gets between the DC and Earth >they could get a lethal shock. I also assume that this power supply >could not drive any I/O ports or displays. Yes. > >Is my assumptions correct Yes. >or can auto transformer power supplies be used more like power supplies >with isolation transformers? NO! I can envisage special conditions where such a technique would be made safe to use, but the risks of those conditions being violated is very high. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk Murphy's Law has now been officially re-named The Certainty Principle 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
