mflux_gamblej
New User
- Location
- Colorado
- Occupation
- Machinist
I just put in a 200A + 200A service (two separate 200A panels in the same building). The inspector had me land my #4 bare from the outdoor ground rods in the two outdoor discos as a separate lug that is bolted to the box. The equipment ground from my pedestal is landed on the box too, but on a different lug and then that has a second lug stacked on it and it then goes inside and lands on my panel (same config in both panels).
My question is, whats the difference here, why would the ground rods be only in contact with the box via the tiny amount of thread (I drilled and tapped a hole for this purpose) that is in the sheet metal of the outdoor disco. Thats it. My ground rods are not tied to my indoor panels by a big #4 for example.
Is there a difference between the outdoor ground rods and the egc in terms of where to land them? It seems crazy to my to ground those two outdoor disconnects but not bother attaching the #4 bare to the EGC to give it the full cross section equivalent as the #2Al EGC. I would think that its better to put them on a big multi port lug so the EGC and the round rods are all tied together with a big cross section conductor. One other detail is that the indoor exposed metal like my water pipe, and I have copper compressed air also, those are tied by a bare #4 to the EGC inside my indoor panel, so these are not tied to the ground rods outside with anything more than that little thread in the sheet metal on the outdoor disconnects.
Thought I'd ask about this, and see what the replies are like. I did not ask the inspector if I should tie these two grounds together in a better way, but it was his suggestion to land the ground rods in the outdoor disconnects with a drilled/tapped hole.
My question is, whats the difference here, why would the ground rods be only in contact with the box via the tiny amount of thread (I drilled and tapped a hole for this purpose) that is in the sheet metal of the outdoor disco. Thats it. My ground rods are not tied to my indoor panels by a big #4 for example.
Is there a difference between the outdoor ground rods and the egc in terms of where to land them? It seems crazy to my to ground those two outdoor disconnects but not bother attaching the #4 bare to the EGC to give it the full cross section equivalent as the #2Al EGC. I would think that its better to put them on a big multi port lug so the EGC and the round rods are all tied together with a big cross section conductor. One other detail is that the indoor exposed metal like my water pipe, and I have copper compressed air also, those are tied by a bare #4 to the EGC inside my indoor panel, so these are not tied to the ground rods outside with anything more than that little thread in the sheet metal on the outdoor disconnects.
Thought I'd ask about this, and see what the replies are like. I did not ask the inspector if I should tie these two grounds together in a better way, but it was his suggestion to land the ground rods in the outdoor disconnects with a drilled/tapped hole.
