Generator running but microwave acting odd

[Jason Worman]

Hi everyone,

So we finally got the generator running well, both A and B legs ample power. Lights on microwave are blinking. When I try to use the microwave it runs but just barely, inside tray turns and stops, turns and stops. Lights on control panel blink. A/C's run fine, space heater runs fine. I turned everything off and just run microwave and still lights blink and strange operation. Turned off generator and plugged back into shore power, microwave runs normal; no blinking lights, light inside unit lights up. When running generator, microwave interior light did not did light up. Any thoughts?

Jason

[Mike Shumack]

Maybe the frequency (60Hz) the generator is putting out is incorrect. Do you have a multimeter with "Hz" setting that you can test with?

Have you checked the voltage at the microwave plug (or any other receptacle) to make sure the generator is putting out 120VAC (+/-10V)? The microwave may be more temperamental with incorrect voltage than your roof AC units.

[Jason Worman]

Mike,

I checked the outlet and its putting out 124.8 volts AC, I checked other outlets and same approximate voltage. Strange happenings. My multimeter does not have Hz reading. When I switched back to shore power, I checked micro outlet and had the same voltage. It is the original microwave.

Jason

[Mike Shumack]

What model Generator do you have? There may be a service manual available.

I have an older model portable gen where the engine speed sets the frequency and voltage - so if the speed control is not working, the frequency can be off.

On my coach's generator it will set a fault code if the frequency is out of range.

[Jason Worman]

Mike

I unhooked and shut off everything, restarted generator and let run 10 minutes and everything is running fine now.
Strange, but everything is working perfectly.Thanks for the help.

Jason