A friend with a Panasonic microwave, Inverter model, physcially a big
one, says it is tripping the circuit breaker after about 5 minutes of
They've reset the breaker several times and it's the same each time.
What's your best guess?
I havent' looked at it yet, but my best guess from afar is that some
of the primary windings in the transformer have shorted, and thus the
impedance of the primary has decreased and it's drawing more current
than it should, more than 15 amps. Does this sound reasonable? If
not reasonable, then possible?
They may have other devices on the breaker which they should remove.
If there are NO other devices on that circuit and you do not have an AC
ammeter, temporarily try the microwave on some completely different
circuit. If that circuit breaker blows too, then the microwave may very
well be bad. OTOH: If it does not blow, then the breaker is weak OR the
wiring going to it is loose or burned and getting hot!
That i thought of, but I didn't get a satisfactory answer. The
electric coffee maker is on the same circuit and they've had to unplug
that, but it isn't plugged in now. But when I tried to bring up other
things plugged in to the same circuit, I got some words I didn't
That I didn't think of, and I should have. He said around 3 that
he'd found one, in the paper or online, a lot like this one, and he
was going to buy one today. I told him I would ask online, but he
still went shopping. I read your replies about 5, and after all of
you brought up the breaker, I called and he wasn't home. I called his
cell and got voicemail. I called his wife at home and he was just
coming in but had to go out and had no time to talk!
She told him it might be the breaker and I could hear him say, That's
a good idea"
I could hear him tell her that the new one was in the car. It's safe
enough he can leave it in the car all night, but I have a feeling he
will bring it in, open it up, and cook something, when he gets home
I was explaining this to the wife, but she raised something I hadn'ty
thought of, and before I discounted it, she'd was in a hurry and said
Maybe I'll know something tomorrow, but experience in general tells me
that when someone gets this head up about buying something, he'll buy
it whether he needs it or not.
Thanks philo and all of you.
If you can get them to go through all those steps I'm sure they will get
it sorted out.
If the do replace the breaker they need to be sure the wire going to it
is not burned...if it is tarnished, the problem will just start all over
Being an inverter model it doesn't have the big transformer in it. Is
it on a separate dedicated circuit??? What wattage is the oven? My
suspiscion would point to the breaker if it is less than 1700 watts
and on a dedicated circuit. If not on a dedicated circuit, what else
is on with it???
We have one like that. There is no big transformer! that is why it's
called and inverter. It's so light, they should move it to another
circuit and try it.
The time delay is the breaker getting warm enough to open. I suspect a
worn out breaker! Replace it and all should be ok.
On Thu, 12 Dec 2013 18:04:25 -0500, Stormin Mormon
You remind me that I had bought a Kill-o-watt, or whatever to measure
wattage. Haven't used it. Only bought it then to put myself over 25
dollars for free amazon shipping. (Now you have to spend 35 dollars
for that) He's supposed to call this morning. I'll suggest it.
Except we'll have to stare at it for 5 minutes to see if it's high
when the breaker trips. Iwonder if it remembers a max value. .
AC clamp on ammeter only goes around one of the
power wires (power or neutral). As such, we use
a splitter, so you can clamp one of the wires
but not the other. If you clamp the entire
microwave cord, you read zero amps of current.
On Fri, 13 Dec 2013 07:17:08 -0500, Stormin Mormon
Oh, yeah. I get it.
I used to have a clamp-on attachment, but I bought a cheap clamp-on
meter from HF and sold the attachment for a dollar at a hamfest.
STill haven't used that either. But I probably will if I live long
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