My welder(that I've had for 3+ years & haven't used yet) has a 6-15 plug on the end of it. The 220v outlet in my garage is a 10-50. Looking at the NEMA chart, the 6-15 has 2-hot wires & 1-ground, while the 10-50 has 2-hot and 1-neutral.
How do I connect the two?
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Do you own the property?
Are you currently using the 10-50 for anything?
Is there a ground wire present?
Assuming that you have no use for a 10-50 outlet, I would replace it with a 6-15.
If you are not super comfy doing electrical, get an electrician to do it.
I agree with 1988RedT2
Turn off the breaker and see what's in the junction box. Assuming you have a ground wire present, wire in a 6-15 receptacle.
In reply to 1988RedT2 & OHSCrifle:
I checked & there is a ground to the 10-50 outlet. I have no clue why the PO put it in the garage & no use for it myself so I'll just swap it out. It's right next to the garage breaker box, so that won't be a problem. Thanks!
Cool. Since IANAE - I'm a little curious what you do with the neutral wire that's in there. Just a wire nut and some electrical tape?
One other thing to check, if you have not already, is that RV/Trailer supply places sell adapters that are often cheaper than a plug or an outlet.