I have never ever seen a Switchmode power supply fail 'high' It's quite possible that sometimes big over-voltage transients may be produced but I have never had anything killed by this myself.
I have seen quite a few of these go boom, sometimes with a very big bang and large mains breakers tripping as a result. My experience ranges from various wall wart type SMPS, Computer supplies, ham supplies and server room 48V supplies I would be interested in hearing of other horror stories 73's Brendan EI6IZ On Tue, 2007-11-06 at 09:35 -0600, Tom Hammond wrote: > Folks: > > A local discussion has 'erupted' regarding switching poser supplies and > whether > they can fail in an UNregulated (e.g. high) output voltage condition, or if > when they fail will they (almost) always fail in a NO OUTPUT mode? > > I think this discussion may have been started as a result of a subject here on > the reflector about overvoltage protection (OVP), but it's managed to take on > a life of its own with respect to the MODES in which a switching P/S > can/will fail. > > Anyone have enough real experience to express their thoughts on this subject. > > Must admit... I have no clue myself. I've 'heard' that most switchers fail in > the NO OUTPUT mode, but this is strictly hearsay. > > Let's try to get several responses and the let the subject drop before IT > takes > on a life of its own on the reflector and Eric has to step in... he's > busy enough > right now. <G> > > 73, > > Tom N0SS > > _______________________________________________ > Elecraft mailing list > Post to: [email protected] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com -- Don‘t complain. Nobody will understand. Or care. And certainly don‘t try to fix the situation yourself. It‘s dangerous. Leave it to a highly untrained, unqualified, expendable professional. _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
