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What gauge wire

01-31-2011, 10:18 AM
I am trying to run wire from my main power box to a sub box in my garage.The distance of wire including extra for hooking it up is 100ft.All the wire gauge calculators say #6 wire,but a welding company I use and some others I have talked to say #2 to be sure its big enough to carry the amperage 100ft.Would #6 be good enough,or should I use thicker?This stuff costs a bundle the bigger the wire gets,and I know they are trying to make as much money as they can off of the wire and I don't blame them,but I am retired and live on a fixed income,at least till I get my welder hooked up.Any suggestions from the pro's that know if #6 is plenty big enough.Thanks guys.
Oh,I forgot to add it's for running 100 amps to the sub box.

01-31-2011, 10:22 AM
You have to consider the amperage more than the voltage for the run. There are online wire gauge calculators you can use to determine what size you need but you have to know what amperage you are going to feed to the substation. Here is a link to a wire size calculator that factors in voltage, current, distance, and wire type. Wire Size Calculator (http://www.csgnetwork.com/wiresizecalc.html)

01-31-2011, 10:51 AM
Thanks Gadget, I edited it to say amperage.I used that chart you posted already and it said #6.I was wondering if that is the bare minimum wire size,or plenty good enough.I need 240 volts and 100 amps at the sub box,and was just looking for conformation that the chart was dead on,or just for reference.

01-31-2011, 11:51 AM
Gilly-- I had a sub panel installed in my garage and the electricain said I would need at least a #4 wire for the run which is about 110 foot from main panel. I had a 100 amp serivce installed. Not sure if it was required by code where I live or the electrcian was trying to make more money off me.

01-31-2011, 03:29 PM
Yea odleo,I think I will go with the #4 wire also to be on the safe side.Thanks for the info.

01-31-2011, 10:34 PM
Glad was able to help.

02-01-2011, 01:27 AM
100 feet 100 amps calls for #4 wire

02-01-2011, 07:06 AM
Thanks my friends,I appreciate it.I wanted to get this right the first time.I should have run a 200 amp service to my garage to start with,and I wouldn't have had to do this again.Oh well,live and learn.