Gareth wrote:

slk wrote:
I have a Panasonic microwave that keeps throwing a 20A breaker. The
data plate on the microwave says it should draw 12.7A max, and an amp
clamp confirms that it's pulling 21A

What could cause this? Is it likely to be fixable by an amateur, or is
the microwave history? It's only about a year and a half old, but it's
been heavily used in an office setting. (maybe it's time to go with a
commercial rated unit)

Microwave ovens have very high voltages inside, thousands of volts,
which can be stored in capacitors even when the microwave is off. There
is also the hazard of high power microwaves leaking out if you don't put
it back together properly.

I would advise you to get a new one rather than risk your life trying to
fix it. Microwaves don't cost much these days so if all the users in
your office put in a few dollars you could get a nice new one.

I second what Gareth says. You can buy a darn nice microwave for less
than $100 these days. Cheaps ones are less than $50. Way less trouble
to buy a new one than try to fix the old one.

Now, with all that said. I would check to see if something is binding
the turntable. Electric motors draw their highest current as
the approach stalling. So gummy stuff in the turntable bearings could
cause a unit to draw high current and *might* be fixable.

I'd still recommend tossing the old one and getting a new one.

Bill Ranck
Blacksburg, Va.