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klem kedidelhopper klem kedidelhopper is offline
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Default Microwave oven troubleshooting

On Apr 1, 8:27*pm, "Phil Allison" wrote:
"klem kedidelhopper"

** *Gotta be a leg pull ???

We got this oven in for repair Its a GE model JE2160SF-03. The name
plate reads 120V 1.65KW (MW). I don't know what the MW stands for
however the 1,65 KW would seem to translate into 13.75A. The line fuse
is 20A. The customer tried to use this with a generator during a
recent power failure. He said that the microwave made some odd noises
as the generator surged a few times and so he disconnected it.


On full power mode the unit draws about 7.0 amps and does not heat the
food.


** OK - *so the magnetron is not operating and you are seeing only the
usual, rather high magnetising current for the transformer. *Attempted use
with a "generator" is the likely cause of the failure cos many small
generators are voltage controlled but not frequency controlled.

The PSU in a typical microwave oven IS sensitive to the AC supply
frequency - *cos it is resonant at 60Hz (or 50 Hz as the case may be).

Operating at a higher or lower frequency then intended will cause serious
misbehaviour of the PSU and in your example this has caused failure of the
magnetron, *likely by over-voltaging the heater.

.... *Phil


But the filament is not open. Lenny