Originally Posted by
Black Diamond
and you're probably used to 480.
Define "used to". Never been hit by 480. Knew some guys that did. No Bueno. I've worked it and am used to that. Most commercial places use 277/480v services mainly for their lighting. LOTS less expensive to run. Receptacles and most usual devices are 120. Some use 240, but that is usually equipment -- two 120 hots and no neutral.
But, the service needs 4 grounds, minimum. Some circuits require individual grounds (separate ground per circuit). Usually hospital/clinics or computer systems.
Oh, and a piece of wood is NOT a ground. Might as well not bother. Just pray the main trips before you get hit.
“When bad men combine, the good must associate; else they will fall, one by one, an unpitied sacrifice in a contemptible struggle.” Edumnd Burke