Wire size calc - two answers

[tklimala]

Working on a homecoming gift for my son - (SGT- USMC)by running electric out to a barn. When I used various calculators I get results of either #4, #2,or #1 wire. Before I ever used a calculator, I had decided on 2-2-2 Al.

Since I am installing a 100 amp panel, I used 100 amps in the calculators - now I am wondering if I should have used a more realistic 75 amps - The largest load would be a 40-50 watt welder - don't own one - but expect that one is in his future.

So with a run of 120' Single phase, 240 volt, 100 amp main, and a nominal load of < 100 amps, is 2-2-2 aluminum adequate?

Thanks - Tom

 

[luke warmwater]

Re: Wire size calc - two answers

The size is OK, but are there any metallic pathways between the house and barn, ie. water lines,phone line,cable,etc...??? The proper grounding is important.

 

[tklimala]

Re: Wire size calc - two answers

No metallic path - water pipe is plastic - I could install a ground rod at each end and tie them together - that would equalize the potential across the network.

[ May 20, 2003, 09:22 AM: Message edited by: tklimala ]

 

[bonding jumper]

Re: Wire size calc - two answers

40-50 watt welder

Is this a new phenominum? A welder that can heat metal to bonding temperatures and use less power than a typical light bulb?

Anyways, sarcasm aside, how far is the barn? is it a long run? Maybe u should use #1 if its a long run, basically because its aluminum wire you want to use. Don't forget penetrox on your connections for that "opps I crapped my pants" extra protection.