B. Adams wrote:
Recently I had a breaker box installed in an outbuilding (Homeline, 70 amps
max, with 2 20 amp breakers). Power is supplied via an underground cable
from the main fusebox in the basement of my house. The distance is around
100 ft and the cable is 12-2 w/ground. I wired the buidling myself
(four circuits, 2 per breaker). The circuits supply 1 light and 1
receptacle in one room and 1 light and 1 receptacle in the other. However,
as there was no ground bar, I tied all the grounds with the neutrals on the
neutral bar. A bonding screw was included but not used. My questions:

1. Does the NEC permit this? Is it safe? (I know that tieing
neutral and ground together on a subpanel in the same structure is a
no-no.)

2. Should the building have its own ground rod? There are no
connections between house and building except for the underground feed.


You need to add a "grounding electrode." (probably 2 ground rods if you
really want to get picky.) If I understand what you said correctly, you
should add the bonding screw in order to ground the metal panel box.

What kind of breaker do you have in the house to protect this circuit?

Best regards,
Bob