On Sun, 03 Jun 2007 01:06:52 +0000, Pop` wrote:

w_tom wrote:


Many power supplies have no fuses. When power supply's output is
shorted, then what avoids a fire or damage? Electronic circuits
inside a power supply make that fuse unnecessary.

Oh, wow! Show me ANY power supply running off the mains that does not have
a fuse/breaker of some sort. It might not be visible and might not be
changeable, but it's there.

I challenge anyone to show me such a supply.


He did not quite say that. he said 'electonic circuits' inside a power
supply make that fuse unnecessary. That circuitry is a form of fusing.
Some companies/industries are not satisfied to do this. We try it in the
auto industry a lot, but OEMs are concerned. Transistors can still
fail-short and this makes it hard to pass cleanly an FMEA (failure modes
and effects analysis) review.