I live in a house that's about 35 years old, and it has a (probably) brand new over the range microwave. I know that the microwave, the overhead light, the refrigerator, and the stove are all on this same circuit. What I'm experiencing is that, if I run the microwave for very long, it trips the circuit. I've noticed that if I only run it for 30 second intervals, it usually doesn't trip it, but occasionally does. It does this regardless of whether I have the light or anything else on (obviously the refrigerator is always on).

Is it likely that the breaker just needs to be replaced or is it likely that it needs to either be upgraded to a 20amp circuit or have a new circuit installed for the microwave? I also have another breaker that tripped just from a light burning out, so I wasn't sure if it's possible that the problem is just that the breakers are old.

Thanks for any suggestions.

You did not mention the breaker on this circuit so I'm guessing a 15 amp. Add up the amps for all of those appliances and you likely reach or exceed the 15 amps. If you run any new cicrcuit I'd try for the frig since it pulls the most. Pull a 12-2 wire from the panel to a new 20 amp receptacle that will replace the old one behind the frig. Hope you have some openings in your breaker box or look for a 20-20 braeker that fits into one slot. You get two 20 amp circuits from this kind.

You need to run a separate circuit for either the fridge or the microwave. Microwave is preferred. Use what the manufacturer recommends. Could be 15 A or 20 Amp.

On rare occaisions a breaker can blow when a bulb burn out. Sometimes pieces of the filament short out the bulb when it blows. Had it happen to a car headlight and my headlights started to blink. Self-reseting breaker popped, light off, breaker cooled, light off, etc.

I'm in the same situation... have a relatively new house (less than 10 yrs old) and in two rooms the burning out of an light bulb will trip the breaker. One guy told me that it could be the ceiling fans have loose
Connections. Don't think that is the problem. Anyone else.. Thanks

Is it an Arc Fault breaker that trips? Should have a test button on the front of the breaker. When lamps burn out, the arcing may be seen by an Arc Fault device as a problem.

Grampy, mine turned out to be a poorly done DIY job by the previous owner. They had too much stuff on one circuit in the kitchen. I had an electrician put the microwave on its own circuit and it's been working just fine ever since.

Grampy, KISS is pretty much right (at least for my situation). The previous owners had presumably installed the microwave to sell the house and didn't bother to test it very well. It turned out that there was too much stuff on one circuit. My electrician put the microwave on its own circuit and it's been working fine ever since.

Thanks.

When we redid our kitchen, I put both the fridge and the micro on separate circuits. I kind of thought that was overkill at the time (following the advice of an electrician friend), but now, after reading this, I'm glad I did it that way.

Knowing what I know, I would do the same. In general the microwave material suggests a separate circuit for the microwave.

The fridge is kind of lame. Nothing much happens to it, but GFCI's sometimes have issues with them.

BUT for backup power, it makes sense to have the micro and fridge on separate circuits because the fridge would be on of those critical loads. The microwave may not be.