[biggun1156]

I am running 220v 100 ft to a 125 amp sub panel. A welder would be the heaviest thing used. (around 200 amp welder) what size copper wire would I need running in pvc underground

[donf]

Well not to be a dull blade, but how do you plan to run a 200 Amp welder on a 125 Amp feeder?

The 125 Amp breaker will not support a 200 amp load.

[stanfortyman]

He means 200A secondary. My stick welder is a 230A welder.

[Missouri Bound]

A 230Amp welder generally requires a 50Amp circuit. And depending on the project it may never be turned up to full capacity.

[biggun1156]

A welder won't draw all 200 amps... im not building ships in my garage. I figure with all my equipment the most I would ever draw would be 50 amps. I just need to know what size wire I would need to run

[tkrussell]

I took the opportunity to measure the amp draw of a 200 amp welder, on a 50 Amp 240 volt circuit, set at the proper welding setting, while a seasoned welder used 1/8" stick and joined 1/4" steel , and got 18 amps.

Based on 50 amps at 120 volts or 50 amps at 240 volts, I suggest #2 aluminum will work fine.

This can be 3-#2 Al with XHHW insulation and 1-#6 AL XHHW Green.

Min conduit will be 1-1/4". I suggest 2" PVC Sch 40 for this length.


The panel in the garage will need a main breaker, ground rod connected to the equipment ground bar for bare or green grounds only, and do not bond the neutral bar to ground.

[biggun1156]

Sir I appreciate your time and thank you for the answer... that is just what I needed

[bungal251]

One must always check the input rating of equipment and not what amperage they expect from the equipment. I once bought a 50 amp breaker as that is standard for a welder. Of course, I was giving the welder its own breaker. I failed to see that it recommended a 60 amp breaker!! All wire ratings are for the amp usage and length of wire. Any workshop or garage should be serviced with 220-240v. This cuts down on amp use and wife loss. Earl