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Cydrome Leader Cydrome Leader is offline
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Default Panasonic microwave, blown inverter board transformer

Chris Jones wrote:
On 18/06/2020 09:50, Jeff Liebermann wrote:
On Wed, 17 Jun 2020 06:55:26 +0000 (UTC), Cydrome Leader
wrote:

[...]
I'd follow these steps too, but I also have the test equipment for doing
so, but OP says they have an inverter microwave. That should scratch the
#2s off the list, which is really easy for for a traditional half-doubler
microwave oven. They have no way to test the HV section safely. Microwaves
are truly the most dangerous electronic appliances to play with.


If you don't know what you're doing, don't have sufficient experience,
can't follow advice, and are afraid of high voltage, perhaps you
really shouldn't be fixing microwave ovens?


It is worthwhile pointing out, at every opportunity, that the electric
shock hazard of working on microwave ovens is extreme, and that
rigourous precautions are necessary. No other appliance that I can think
of has the combination of high enough voltage to shock severely through
clothing and dry skin, enough current to certainly kill someone, yet
some current limiting and isolation from the mains such that a RCD or
circuit breaker will not trip to save you.


That's a good point too. All the service tech microwave oven deaths in the
US I'm aware of were people getting dead from the capacitor, with the unit
off. apparently those caps are perfectly sized to just stop your heart.
You'd get noticed about who croaked last in the trade bulletin/sales
"newsletters" that got mailed out every few months.

No doubt if you were getting electrocuted off a running microwave, the
fuse would never blow. I have a large transformer for what I'm told is an
industrial microwave something device. The transformer doesn't even have
shunts and outputs a full 4kV at a couple kW. It makes for one of the
fiercest jacob's ladders I've thrown together.