In wiring a storage building from home panel I`m running 100 amp service to it 4 wire use now I`m not sure do I drive a ground rod or 2 ground rods or does the 4th egc wire take care of it. Thanks in advance
Reel, 99 code 250-32. If your building has more than one ckt (and I'm pretty sure we can assume it does) you have to have a grounding electrode (rod, water pipe, effectively grounded bldg steel, etc.) connected to your green, bare, whatever grounding conductor.
Using 4 conductors, your neutral and ground are kept separate at the out-building service, but the ground must have an electrode.
