Home wiring: What circuit is preferential for a microwave?

Originally it was going to be on it's own circuit and I was going to have the disposal and dishwasher be on the same circuit. Unfortunately now I realize I can't steal the wiring from either the disposal or the dishwasher. So the options are:

A: Circuit with one wall plug (currently powers a subwoofer), kitchen island outlet and a refrigerator.

B: Countertop outlets, a wall plug that powers my TV/stereo,

C: Keep it where it currently is which has guest bathroom, hallway lights (will be converted to LED), kitchen lights, one exterior plug and one exterior flood light.

It's tripped the breaker a few times as is. That will be somewhat remediated once everything gets converted to LED but I still don't think it's ideal.

I'm thinking A or B. Probably A since the fridge is brand new and doesn't draw much and run the risk of tripping the breaker if I had the microwave going along with a blender or 4 on the countertop outlets.

If your panel has room, run dedicated ckt for the microwave

All of my home circuits are 60hz, wavelength of approx. 5 meters so none of them are even close. You should be careful transmitting microwaves from your home electrical circuits. You will get the cancer.

Are any of these circuits using #12 wire? What size breaker? What does your microwave draw?

Micro can share the counter top if its on #12 wire. Leave the fridge solo. Bathroom etc looks busy enough.

Don't share the fridge circuit because of you do blow it and don't realize right away you can have ruined food. It would be fine most of the time I'm sure but why take the chance?

I vote for option b. Microwaves don't draw a huge amount, so it should be fine.

Yeah, I'm, with B. What all is on the breaker it is tripping? It shouldn't draw more than 15-ish amps, I would think. That's like 1500-ish watts. What's the power spec on the microwave?

1500 watts should be in the neighborhood of 12.5 amps.. it varies as no place has a steady 120v

dculberson wrote: Don't share the fridge circuit because of you do blow it and don't realize right away you can have ruined food. It would be fine most of the time I'm sure but why take the chance?

Could you really blow a circuit while heating something in the microwave and not notice?

Option B if it is a countertop microwave. If it is a built-in unit electrical code requires a dedicated circuit.

In reply to mazdeuce:

With kids around? Yes.

It is a built in. Half ass added before we bought the house. I originally planned on stealing the circuit for the disposal but then i found out the disposal/dishwasher share a 12(i think)/3 wire that gets split up at the disposal switch.

I'll add it to the countertop circuit (B). The way it's mounted I can actually run a new line to it later if I replace the panel or find some other way to free up space without tearing up the drywall.

I'd look closer look at that disposal circuit. You won't be running all 3 at once and a #12 with a 20amp breaker will carry a lot.

The dishwasher and disposal circuit is likely run in 14/3. You might be able to jump off of the disposal side, but not the dishwasher side. I would still stick with option b though.

Did the range hood vent not have it's own dedicated circuit? I used the range hood 12/2 20A circuit for my microwave and new vent hood when I redid my kitchen.

If the microwave isn't on a 20A circuit your going to have issues.

Ended up going with option B. I believe its a 30 amp circuit but will confirm.

What happened with the previous owner is there was likely a under cabinet range hood there. When the house was foreclosed on Fannie May installed a microwave there as part of their homepath program. Being that a microwave is much larger than a range hood it was only like 14" off the top of the range. That microwave shared a circuit with option C above. It was on a outlet fed with 14x2 and the outlet was mounted in a electrical box that was just mounted to the side of the cabinet with 14x2 sticking out.

I ran all new plugs and wiring to the countertop (now every part of the counter is within 2' of a plug) and one of those plugs is mounted higher up where the microwave would go. It's not a dedicated circuit but still an improvement over before.

First time doing a lot of these things so please point out what i'm doing wrong. I don't mind redoing work. I'll get a build thread going soon.