Just out of curiosity I had a look at a welder from same manufacturer with twice the rated input - and same 50 amp 250 volt plug on it. And I agree, why run the #6?
So it comes out of the factory as "listed and approved" equipment with one oversized plug that fits all. I could go and change out the plug on this approved and listed piece of equipment but then I am interfering with the approval - ironic.
