Microwave Wiring

[djcjking]

Is it to code to wire a 120 volt outlet for a mircowave to and 240 volt 40 amp oven outlet?

 

[charlie b]

I don't quite understand. Clearly, you can't apply 240 volts to a 120 volt microwave. What exactly are you trying to describe, and how does this situation arise in your contracting business?

 

[Dennis Alwon]

Is it to code to wire a 120 volt outlet for a mircowave to and 240 volt 40 amp oven outlet?

Most microwaves are 120 volts and most ovens are 240 volts. Whether it is 30 amps, 40 amps or more depends on the KW of the units. Many 240 volt single ovens only need 30 amps while most double ovens need 40 amps and sometimes 50 amps.

 

[lpelectric]

Is it to code to wire a 120 volt outlet for a mircowave to and 240 volt 40 amp oven outlet?

It is very common to see microwaves come as cord-and-plug connected appliances all set to be plugged into 120 volt receptacles. Othertimes, a microwave may be hard-wired in accordance with it's listing and/or labeling. Usually they're still 120 volts, though.
Ovens typically are 240 volts and require a neutral (grounded conductor) and an equipment grounding conductor, too.
Do not attempt to wire the 120 volt microwave off from the 240 volt oven circuit. Not good.

 

[480sparky]

Could this possibly be a stacked unit, a micro on top of a conventional over? All of them like that I've ever seen have one 240V, 4-wire connection.

 

[lpelectric]

Could this possibly be a stacked unit, a micro on top of a conventional over? All of them like that I've ever seen have one 240V, 4-wire connection.

Me, too. :smile:

 

[Dennis Alwon]

Could this possibly be a stacked unit, a micro on top of a conventional over? All of them like that I've ever seen have one 240V, 4-wire connection.

It could be but then why would he be asking about 2 different voltages? Until the op comes back we may never know.

 

[fisherelectric]

I can tell you, from experience, that a microwave will only run on 240v for about a milli-second.

 

[wirebender]

I'm pretty sure he's asking if he can install a 120v receptacle for the microwave by tapping one leg of the oven circuit.

No, you can't.

25 years ago, I re-wired my house. Behind the range I found a 10/2 openly spliced (no box) to the range and two 12/2s which went to the fridge, hood and all the kitchen receptacles, one of which had a microwave plugged into it. Used the bare for the grounded conductor.

Never tripped that breaker. FPE made some fine equipment back in the day.:roll:

 

[Rewire]

I can tell you, from experience, that a microwave will only run on 240v for about a milli-second.

If you run a microwave oven on 240 while looking in a mirror and taking your picture with an instant camera you will time travel.

 

[LarryFine]

If you run a microwave oven on 240 while looking in a mirror and taking your picture with an instant camera you will time travel.

Yes, but will any light leave the flashbulb?

 

[wbalsam1]

If you run a microwave oven on 240 while looking in a mirror and taking your picture with an instant camera you will time travel.

Adjusting the f-stops will dictate where you travel to.

 

[rcarroll]

Yes, but will any light leave the flashbulb?

It depends on which direction you travel. :roll:

 

[wirebender]

Adjusting the f-stops will dictate where you travel to.

Don't go back to a time before microwaves! Unless you want to stay.

 

[RayS]

Don't go back to a time before microwaves! Unless you want to stay.

lol. that's good.

 

[KJay]

I can tell you, from experience, that a microwave will only run on 240v for about a milli-second.

The OP didn't say if this was a residential or commercial installation.
Many dual magnetron microwave ovens used in commercial kitchens have a switch under a coverplate in back to select either 208V or 240V single phase.