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Posted to sci.electronics.repair
Rob Mitchell
 
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Default microwave oven Sharp R-650D

This 2 year old oven failed last week. ALL the appliances in my house
are dying - central vac, dryer, fridge, wall oven, microwave within 3
months. Even my alarm clock is threatening to die. The dryer, fridge
and oven are the same age, but the vac is much older, micro and clock
much newer. Is there anything that could cause mass appliance death?

After reading sci.electronics.repair.faq for mwaves, I found that one of
the relays was about 300 ohms across the contacts when it was off. I
replaced it with the closest I could find (24VDC coil, 40A AC contacts).

Now, after re-assembly, the oven looks dead. However, if I open the
door, the display turns on welcoming me to set the clock. I set the
clock and then when I close the door, the power goes off, and it's dead.

Open door, set clock, close door can be repeated. No fuses or breakers
blow. When the door is open, the light comes on.

I thought that perhaps the coil resistance might not be a good match.
The old one was 1.1K and the new one was 650 ohms. So I added 600 ohms
in series. Now, I hear the relay pull in, and the microwave no longer
turns off when you close the door. The control panel 'works' but there
is no energy, the turntable doesn't turn and the fan doesn't come on.

Without drawings this is like working in the dark.

What I really need is an OMIF-S-124LM, but delivery is 20 wks and I have
to buy 50 groan. Any suggestions or help very welcome.

Rob