One thing to remember about building codes, including electrical, is that they are MINIMUM codes. That is they are the bare minimum that you can legally get away with.
Your panel may well be up to "code" for you locale, but I'd still put in the ground rods at the outbuilding and separate that "real" ground from the neutral running back to the house.
With something that can burn your house down or electrocute you I'd go better than code, by a couple of steps.
|