What size wire for 250ft run?
#1
What size wire for 250ft run?
I need to run electric to my shed which is almost 250ft from the main panel. I need a minimum of 20amps (120) there so I can run a table saw, but ideally, I'd like to get install a 50amp sub panel. So what size wire do I need?
A friend of mine says if I want 20 amps, all I need is 8awg copper, but the online calculators keep telling me either 3 awg for aluminum or 4 awg for copper.
What is correct?
Thanks!!
A friend of mine says if I want 20 amps, all I need is 8awg copper, but the online calculators keep telling me either 3 awg for aluminum or 4 awg for copper.
What is correct?
Thanks!!
#2
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You are correct, if you really want 20 amps available on a 120 volt circuit and wish to keep voltage drop to less than 3 percent.
However, you can do much better than that.
Look for aluminum mobile home feeder cable, and use that to run a sub panel.
However, you can do much better than that.
Look for aluminum mobile home feeder cable, and use that to run a sub panel.
#3
Agreed. Use a #2-2-2-4 aluminum mobile home feeder direct-burial cable with a 50A subpanel. It's sold as a 100A cable, but should only be used for 50A at your distance. The #2 aluminum cable probably isn't too much more expensive than the #8 copper.
#4
Thanks folks... I guess I'll need to find a low cost source for some 2224. It's going to cost me way more then I want to spend, but it's way cheaper then copper.
#8
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The voltage drop is the same, but is less of an impact. For example, a table saw at 120v may pull 16A, but at 240v will only pull 8A. 16A over a long distance will have more of a voltage drop than 8A.
So my understanding is that all else being equal, wire larger equipment at 220 vs 120 (presuming it's designed as such).
So my understanding is that all else being equal, wire larger equipment at 220 vs 120 (presuming it's designed as such).