Elec Question-Stove, uwave 220/110V

A friend of mine asked me a question I didn't know the answer to, so I told her I'd ask you guys.
She has a stove-oven/microwave combination. She is going to get a new stove/oven and a microwave but the microwave will be separate. Currently (heh) she has just the 220V outlet for the stove. Can she take one leg of the 224V circuit and run an outlet for the microwave? Her reasoning is that she should be able to since it was done before, just inside the stove.
What say those more knowledgeable?
--
charles

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Don't know about those more knowledgeable, but I say NO. Before ,the microwave was integral to the stove, and U.L. approved as a unit. It was also probably fused inside the stove as well . In any event she'd now need to run a dedicated circuit for the microwave

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Charles Bishop wrote:

NO. The stove breaker would allow 40 or 50 Amps before it trips. Wiring for the microwave would only be 20A or even 15A. An overload on the microwave could cause a fire. I am pretty sure a tap off is not allowed even if you were to add a smaller breaker after the stove outlet. Also some older stove outlets do not have the neutral wire that would be needed for the 120V.
Kevin
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Charles Bishop wrote:

Not a good idea.
Run a separate 20 amp 12 gauge line from a breaker serving only the microwave.
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Or see if the new stove has a 120V outlet on it that's rated high enough for the microwave (check the instructions). Stoves always used to have one, but auxiliary outlets are a lot rarer these days (if not non-existant).
Even if it does, she might consider the cord over the top of the stove objectionable anyway.
Running another circuit is the best way. Electrical codes forbid the use of 120V and 240V devices on the same circuit _except_ when the 240V device has a UL/CSA approved 120V outlet on it. While the codes will permit turning a four wire 240V/120V stove circuit into a feed to a subpanel (with its own breakers) to supply both 240V and 120V, that will NOT be permissible with an old style 3 wire stove feed, and probably not with 4 wire unless the circuit ampacity is enough for _both_ the stove and microwave circuits simultaneously at full. You might get away with a 4 wire 60A feeding a breakered-for 40A stove and breakered-for 15A microwave circuit, but 60A stove circuits are rather rare - the more normal 40A stove circuits for 40A stoves aren't enough.
In Canada, builtin microwaves have to have their own dedicated circuits anyway. That may be true now in the US as well.
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
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No. The microwave must be on a 120 volt 15 or 20 amp circuit depending on the unit's nameplate rating. I am familiar with these types of changeouts because those combo units were installed in quite a few townhouses in my area that I service. In most cases I have found that there already is a 120 volt 20 amp circuit wire in the wall above the stove. I surmised that the electricians who wired these units were told to wire for a hood fan or a microwave and installed the wiring for such during their rough-in. You might want to investigate that.
When my customers change from the combo stove/microwave to a separate stove with a overhead microwave, they usually have to get some overhead cabinet work done. The new microwave is supported by a wall bracket and by two long bolts that come through the shelf inside of the top cabinet. In the cases that I have seen there is no top cabinet, just a fascia board that matches the cabinets. Your friend may have a similar situation.
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In article
snipped-for-privacy@earthlink.net (Charles Bishop) wrote:

Thanks for the replies. She's going to run a separate circuit.
--
charles

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