wrote in message
oups.com...
Upon power-on, the unit runs thru a series of beeps and buzzes (normal,
as I recall), then the overload indicator lights up and the unit beeps
continually.

Is the unit toast, or is there a relatively painless fix?

Thanks.

----dale

I've worked on one of these. First off, APC is NO HELP whatsoever, they do
not, will not, give out any technical info. The extent of their "technical
service" is a trade-in program whereby you donate your slightly damaged unit
to them and they sell you a brand new unit for nearly full price. They
guise this as "protecting their proprietary technology" even if you're
trying to fix a unit that's 20 years old.

Check your output transistors... they are likely 60A N-channel enhancement
mode mosfets and they ain't cheap. The unit I worked on smoked 8 out of 16
of them. They are riveted to 4 heatsink plates and soldered to the board.
Be REAL careful removing them as the tiny hair-like board traces tend to
like to come with them.

Dave