I have a generator which is capable of 480/277 3P and 120/240 1P . Neutrals are bonded to generator frame.
Q. Pump station is fed 480 Delta 3wire no ground from utility. Ground rod at serice equipment ground run to station disconnect/transfer switch.
Since there is no return to the utility transformer. I believe a ground rod should be driven at the trailer mounted generator. The generator has a 4 wire 3 phase cord supplying the pump station .
The second pump station is a 4 wire 277/480 wye system neutral is unbroken in the transfer switch.
Here I believe a rod is not required at the trailer.
The generator rep. has instructed a ground rod be driven in all cases. I believe in some cases he is greating a parralel ground path.
Q. Pump station is fed 480 Delta 3wire no ground from utility. Ground rod at serice equipment ground run to station disconnect/transfer switch.
Since there is no return to the utility transformer. I believe a ground rod should be driven at the trailer mounted generator. The generator has a 4 wire 3 phase cord supplying the pump station .
The second pump station is a 4 wire 277/480 wye system neutral is unbroken in the transfer switch.
Here I believe a rod is not required at the trailer.
The generator rep. has instructed a ground rod be driven in all cases. I believe in some cases he is greating a parralel ground path.