Microwave trips breaker, but only on generator.

[dtfeld]

I have what I assume is the original microwave, Panasonic 1300W inverter. Works fine at the dock on shore power, but last week-end, it was tripping the breaker while running on the generator. That load should pull 10-11 amps. However, it would jump (watching AC Panel meter) in approximately 5 amp increments until pulling 20-25 amps. I shut everything else on that side to isolate the microwave while diagnosing

Anyone had this situation? I would think I have 1) a bad microwave or, 2) bad power from the generator or 3) a bad breaker?

Was considering replacing microwave with a micro/convection unit anyway. Anybody made this swap, and what model did you go to?

 

[The Bill Collector]

We replaced convection/micro with another Sharp and didn't take too much adjusting to get it in the cabinet.
http://www.clubsearay.com/index.php?threads/sharp-convection-microwave-replace-repair.15514/

 

[dtfeld]

We replaced convection/micro with another Sharp and didn't take too much adjusting to get it in the cabinet.
http://www.clubsearay.com/index.php?threads/sharp-convection-microwave-replace-repair.15514/

Thanks Bill Collector. I've been looking at these threads, seems every model mentioned is no longer in production, I guess the life cycle is about 2 years these days.

 

[The Bill Collector]

Thanks Bill Collector. I've been looking at these threads, seems every model mentioned is no longer in production, I guess the life cycle is about 2 years these days.

Sorry, I found my order at Amazon and it is not being offered any longer. https://www.amazon.com/gp/product/B00007BGTL/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

 

[Boater420]

Have you measured voltage/Hz at a receptacle? If you're putting out less than 60Hz that might be your problem if it works on shore power and not the generator. If you have a generator this should be one of your test tools.

60 Hz is what you're looking for at the outlet.

 

[dtfeld]

Sorry, I found my order at Amazon and it is not being offered any longer. https://www.amazon.com/gp/product/B00007BGTL/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

Found an old manual for that unit...it could be built in.

I'll have to keep looking for something similar. Everything these days needs about 10" above the unit for cooling.

 

[dtfeld]

Have you measured voltage/Hz at a receptacle? If you're putting out less than 60Hz that might be your problem if it works on shore power and not the generator. If you have a generator this should be one of your test tools.

60 Hz is what you're looking for at the outlet.
View attachment 57611

I'll put my meter on it next time back.

 

[sbw1]

Microwaves pull lots of amps when the magnetrons come on. This is normal. We have to turn our water heater, cockpit heater and water heater off when we make breakfast and coffee at the same time. Otherwise we trip the breaker. Just because yours is doing this does not mean it is defective. You need to manage the loads on the genny.

 

[superwa]

Mine actually shuts off if I don’t have other items pulling amps. Not sure why. So I usually turn on the water heater before using the micro. Thinking that it needs the gen to rev up a little up front

 

[dtfeld]

Well, tested it today at the dock. Ran just fine, pulled a little over 10 Amps just like I thought it should. Ran for several minutes. Amp meter wasn’t jumping around either

Also checked the generator. Under load it’s 125v and 60.11hz. Just about what the power at my house is.