Convert 3-wire 240v to 120v

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  #1  
Old 04-20-13, 06:31 AM
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Convert 3-wire 240v to 120v

I have looked around on this site and found several postings that are similar but not one that matches my situation. I am replacing a 1986 electric stove that used 3-wire 240v with a gas stove that needs standard 3-prong 120v. The existing wiring for the stove is three large gauge copper wires - two black and one bare. The wires are not solid copper but braided smaller wires. They come off a double prong 30amp breaker to which the two black are connected and the bare is on the neutral bar. How would I go about converting that to 120?
Thank you.
 
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Old 04-20-13, 07:28 AM
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By code you can't because a bare wire can't be used as a neutral and a wire #6 or smaller can't be remarked as a neutral so you can't use one of the blacks as a neutral.

If this is conduit you can use one of the black wires to pull in a white wire as you pull the black wire out.
 
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Old 04-20-13, 07:32 AM
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Welcome to the forums!

You will need to change the breaker from the two pole, 30 amp, to a single pole, 20 amp. One of the wires will connect to the breaker. The other will need to be marked white, if it is not already, (Wires in a cable may be re-identified) and connected to the neutral bar. If this is not the main service panel, you will need to move the bare wire to the ground bar.

Then it is best to connect short "pig tails" of #12 wire off the larger wires as the larger wires will difficult to connect to the new receptacle. You will need a proper box to connect the new receptacle to. Use a meter between ground and one of the insulated wires to find which one is neutral, and connect that to the silver screws of the device.
 
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Old 04-20-13, 08:01 AM
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Mark, your post is a bit ambiguous. Tolyn read it as you having a cable whose white was remarked black. I read it as you having conduit with two factory black wires. Which is it?
 
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