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Length of Run in Feet

Compare size below with size left of double line and use largest size

50 75 100 125 150 175 200 225 250 275 300 350 400 450 500 550 600 650 700
14 14 14 14 12 12 12 10 10 10 10 8 8 8 8 8 6 6 6
14 14 12 12 12 12 10 10 8 8 8 8 6 6 6 6 6 4 4
14 12 12 10 10 8 8 8 8 8 6 6 6 4 4 4 4 4 3
12 10 10 8 8 8 6 6 6 6 4 4 4 4 3 3 2 2 2
12 10 8 8 6 6 6 4 4 4 4 3 3 2 2 2 1 1 0
10 8 8 6 6 6 4 4 4 4 3 2 2 1 1 1 0 0 0
10 8 6 6 4 4 4 4 3 3 2 2 1 1 0 0 00 00 00
8 8 6 6 4 4 3 3 2 2 2 1 0 0 0 00 00 000 000
8 6 6 4 4 3 3 2 2 2 1 0 0 0 00 00 000 000 4/0
8 6 4 4 4 3 2 2 1 1 1 0 00 00 000 000 000 4/0 4/0
8 6 4 4 3 2 2 1 1 1 0 0 00 000 000 000 4/0 4/0 250
6 4 4 3 2 2 1 1 0 0 00 00 000 000 4/0 4/0 250 250 300
6 4 3 2 2 1 0 0 0 00 00 000 4/0 4/0 250 250 300 300 300
6 4 3 2 1 0 0 00 00 00 000 4/0 4/0 250 250 300 300 350 350
4 4 2 1 1 0 00 00 000 000 000 4/0 250 250 300 300 350 400 400
4 3 2 1 0 0 00 000 000 000 4/0 250 250 300 350 350 400 400 500
4 3 1 0 0 00 000 000 4/0 4/0 4/0 250 300 350 350 400 500 500 500
4 2 1 0 00 000 000 4/0 4/0 250 250 300 350 400 400 500 500 600 600
3 1 0 00 000 000 4/0 4/0 250 250 300 350 400 500 500 500 600 600 700
2 1 0 00 000 4/0 250 250 300 300 350 400 500 500 600 600 700 700 750
2 0 00 000 4/0 250 250 300 350 350 400 500 500 600 700 700 750 800 900

Procedure: Find the amperage in the left column and the length of run along the top of the table (if between two of the table values go to the higher value). Where the two intersect on the table is the recommended wire size that will keep voltage drop within acceptable limits. Compare the recommended value on the right side of the table to the value shown on left side (minimum NEC requirements for the insulation type to be used) and use the larger size.