ground wire size

[spencersct]

I am installing an 60amp three conductor sub-panel 700feet from main panel. Because of the distance I am using #1 feeder wires. How do I calculate the ground wire size?

 

[augie47]

ground wire

ground wire

You increase the kcmil of the required equipment ground by the same percentage that you increased the phase conductors.
(Compare the area of the #1's you are using to the required #6. Use that same percentage as a multiplier for the area of the required #10)

 

[steve66]

See chapter 9 table 8 to convert the #1 and #6 to circular mills. #6 is 26240 and #1 is 83690 so you have increased your wire size by about 3.2 times.