View Full Version : Hydro Rating

05-08-2006, 02:18 PM
I have 3.0 wire 90 feet long running from my home to my shop. It currently is fused for 30 amp usage. I am upgrading to five horse compressor and a 250 amp (hopefully miller mig welder) Can i run more than thirty amp through this 3.0 wire its quite fat looking. Thanx Mike

Rich Carlstedt
05-08-2006, 02:45 PM
You didn't say if it was Copper or Aluminum ?
A number 3 Copper wire is rated at 80 Amps buried or 120 amps when
strung between poles.
I would say you are covered as the distance means little with the loads you mentioned.
Your Welder probably will draw 60 amps at 220 when it is fully loaded.

05-08-2006, 02:53 PM
Is it 3 gauge or 000 gauge. There's a BIG difference. If it's 000, you can probably run a full 200A circuit feed for the shop. If it's 3ga., the max is about 75A. (Copper)

05-08-2006, 11:17 PM
Does he mean that there are 3 one ought (0) OR 1 3 ought (000) or possibly one #3 (?) conductor (kinda a rare bird) . With out a better description everyone is just shooting in the dark.


05-09-2006, 01:10 AM
I don't think he means 3 point 0, he means 000, and I don't think he has run one conductor of it. Hard to complete a circuit, especially 220 with one conductor.

Until he posts again, we should assume he has run 3 wire, 3/0 with maybe a 2/0 neutral. Not 200 amp, but I do think good for 150. 200 is 4/0, I do believe, at least in aluminum. Come to think of it, copper and Al are the same ampacity, different diameter, Al is fatter.