[Elecraft] Anyone know this info about switching supplies?

[Brendan Minish]

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
> 
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