construction trailer

[jackman435]

We are hooking up a 100amp, 1 ph 120/240v load center in a trailer on a const. site. We are installing a 100 amp fused NEMA 3R disconnect on a pole 10' from trailer. We will use USE to feed the load center. My question has to do with grounding. Does the Load center require an isolated neutral bar, with neutral going back to disconnect, and a ground bar with EGC also going back to disconnect? Not sure if this should be treated as a subpanel.

 

[kwired]

We are hooking up a 100amp, 1 ph 120/240v load center in a trailer on a const. site. We are installing a 100 amp fused NEMA 3R disconnect on a pole 10' from trailer. We will use USE to feed the load center. My question has to do with grounding. Does the Load center require an isolated neutral bar, with neutral going back to disconnect, and a ground bar with EGC also going back to disconnect? Not sure if this should be treated as a subpanel.

Unless you are on old NEC (has to be 2005 I think or earlier) you can no longer run a feeder to a separate building or structure and use one conductor for both grounded conductor and equipment grounding purposes. Depending on circumstances back then you may still have needed 4th conductor for grounding but now none of that matters anyway - 4 conductors is needed.

The 3 conductor situation is only allowed to remain for existing situations where it was originally allowed, which you don't have.

 

[jumper]

I know it is only 10' but code would require a GES also.

I wonder, since it is only 10' if code would allow you to run the trailer GEC over to the electrodes at the disconnect.

Can two structures share one GES?

 

[ActionDave]

Can two structures share one GES?

Sure.