I have a 500? overhead run to a temp trailer. 120/240 volt. Do I use 3 wires and ground rod or 4 wires and a ground rod?
That is what I think but I am not sure? (05) Look at 250.32 (1) & (2)
I have a 500? overhead run to a temp trailer. 120/240 volt. Do I use 3 wires and ground rod or 4 wires and a ground rod?[/QUOTE
It looks like exhibit 250.17 in the NEC handbook only shows 3 wire for the feeder from panel in one building to panel in another building there is a neutral but no EGC but each panel has a ground rod. That is very confusing because a mobile home fed from a disconnect on a pole requires 4 wire with ground rod at disconnect but not at trailer panel
I ordered the 4 wire just to be sure. But I still think 3 wire and ground rod are ok.