I hope this helps, the breaker is a double 40 it has 4 wires 3 of which are about 3/8 inch in diameter or so ,sorry unsure what gauge. And the bare ground wire. Note: nothing else on that breaker. The outlet is a 30 amp 125/250 volt4 hole. Again I would like to change this to a 3 wire plug to power a welder that is a 230v 50a 60h single phaze input, I hope this is better info than my first question.

Does your welder

Youn eed to verify the size of the wire going to the existing plug. You will need to use #6 wire to carry the 50 amp load. Does the welder require a 3 or 4 prong receptacle?

Dwayne,

You need to stay in one thread. You are all over the place. You do not have to start a new thread to post answers, or questions.



Missouri,

If I used #8 THHN for my arc welder, what size (Max size) OCPD can I use?

Dwayne, can you post the model number and manufacture name of your welder. Just want to verify your information.

Thanks!

PS: A 3/8 diameter is close to being a #6-3NM-b or closer to being a #6-2NM-b<<<yet, don't go installing anything. I agree with Missouri, that wire needs to be verified.