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old 240 v welder 3 wire plug - outlet is a 4 wire

Posted by ross_2010 (My Page) on
Sat, Aug 7, 10 at 20:11

I recently purchased an old 200 amp mig welder which requires a 240v supply. I have an existing 240v outlet that was for my range (before i got a gas range). Since the wall that outlet is on shares a wall with the garage, I will basically turn the thing around and use it for the welder. However, the outlet is wired with 4 wires and the welder only has three. I have read numerous thoughts on the conversion and many of them oppose one another. I would like to get a difinitive, and safe answer for how to set up the wiring.

Follow-Up Postings:

RE: old 240 v welder 3 wire plug - outlet is a 4 wire

The welder most likely has the two hots wires and a ground. The range receptacle has two hot wires, a ground, and a neutral. You just don't connect anything to the neutral, it doesn't need or care about it.

RE: old 240 v welder 3 wire plug - outlet is a 4 wire

thank you Ronnatalie. Jist to be clear - the 4 wire is black(hot), black/red(hot), grey(neutral), and bare(ground) correct?

RE: old 240 v welder 3 wire plug - outlet is a 4 wire

Yes, sounds rihgt. Green or bare is always ground. White or gray is always neutral. Other colors are fare games for the hots (black, red, blue, ...).

RE: old 240 v welder 3 wire plug - outlet is a 4 wire

I bought a 50 amp 4 wire plug to match the outlet and wired the 3 wires the welder had, and left the neutral post empty just like you said... works perfectly! Thanks for the help!

RE: wiring 240 L14/20 plug

I am making an extension cord for my generator. I want to wire it for 240. Can I use a 12/3 cord and wire a jumper to the second hot leg??. Please advise..thanks for your time.

RE: old 240 v welder 3 wire plug - outlet is a 4 wire

You'll have to explain yourself more, but I suspect the answer is no. And frankly, this has nothing whatsoever to do with the thread that you posted it in. It would be better if you started your own.

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