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Brad S
02-27-2010, 12:35 AM
Running a 220 outlet to the garage in my new house for a welder and I need some help figuring wire gauge. Here's the specs from the welder's operating manual:

http://x4m7qg.blu.livefilestore.com/y1petz8m1CPWZBejlvqmFuhkHte1rBa0v4qUuu6cwKFCViwOhD UKGWP8O9d1oskc4sn56bO8BkTf7p1SJ04ECrQRmLEqtM2eMOq/welder-specs.jpg

From that I see that I need a 40 amp breaker and a 50 amp three prong plug (which matches what's on the welder), but now to calculate wire gauge...

I've looked at several calculators online but get varying results as to what gauge to use. It's going to be about 30 ft from the main breaker box to the garage outlet. I was thinking 8-3 wire since it says input is 20 amps, but is that still not enough?

I was reading some posts earlier about some of you wiring this up, so any hindsight advice from the jobs you finished?

grnd93
02-27-2010, 11:59 AM
Look up your local electrical code. 8 guage is probably the minimum requirement, but I'd probably go with a 6 guage. Remember the type I wire makes a difference as well.