Re: microwave - no power

On Wed, 19 Apr 2006 02:08:48 GMT, Rich256 <nospam@xxxxxxxxxx> wrote:

Charles Bishop wrote:

Is it likely I'll recognize the fuse? A flashing neon sign: "Fuse"? or do
I have to look around. The likeliest place I'd think would be just after
the line cord comes in.

The ones I have seen are the normal Buss type and usually mounted in an
open area on the chassis. Usually it is a slow blow or thermal type.


Just did a bit of searching and found some URLs you might take a look at:

http://www.everist.org/special/mw_oven/

http://home.cvc.org/microwaves/how_work.htm

Another thought. Not likely problem, but are you certain that the
breaker to the oven has not tripped? It could be on a breaker by itself.

I just recalled fixing one of the first Armana ovens. It was one of
those with a chrome door similar to the front end of a '55 Buick.

The power line ran through a hollow ceramic resistor that had one of
those one shot, thermal overload relays like you find in coffee pots.
The resistor was in the power line to the magnetron. If the magnetron
drew too much current the resistor got hot and blew the switch.



Over a period of time, the magnetron may draw more current as it ages.
This may or may not be enough to blow the fuse. According to most of
the websites I've seen, the main fuse is the most common problem, with
75% of the faults caused by aging, high resistance fuses, or trouble
with the door interlocks (microswitches).

The microswitches can arc over internally, if they frequently break
any substatial amount of current.

Incidently, on most ovens, one of the microswitches is the fail-safe
"idiot" interlock microswitch which causes a direct short across the
AC power leads, should the door not be closed and if the magnetron
relay actually is in the ON state.

Beachcomber



I had to search around to find a replacement relay with the same
temperature rating. Replaced it and the oven worked for a few more years.

.

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