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	Subject - Service Grounds David Hyatt OK, I have a meter (3phase), 200 amp disconnect, 200 amp panel backed up inside building behind disconnect. I run 3 (3/0) phase conductors and 1 (3/0) neutral in a two inch PVC between the meter and disconnect. Then a 2" pipe out of disconnect to panel with 3 (3/0 phase conductors and 1 (3/0) neutral and #4 green. I bonded the disconnect but not the panel board. Heres my questions. All wires are copper. 1) Tbl 250.122 says I could use a #6 ground from disconnect to panel, right? But the grounding electrode conductor in Tbl 250.66 requires a #4, so it actually has to be larger than the service panel ground. This seemed strange.? 2) The plans call for the water pipe ground, ground rod, and building steel to come from the outside disconnect not the panel. It will be a lot easier to come from the panel, is this not the same thing? Instead of feeding through the disconnect and through the panel to building steel.I also think I will take the ground rod ground wire from the meter can. 3)The panel is bolted to the steel structure with 3/8x4" bolts, is this not sufficient enough ground or do I need to run a wire from the panel to building steel. Seems like a useless thing to do? The panel is bonded and bolted already. Will this meet code? All feed back on this topic will be appreciated, I have to go back tomorrow. I need to make sure I am doing this right. Thanks. 4) Instead of just running a bare ground to ground rod exposed, should I install it in conduit? Never done that but may look better. Dave Nix 1) Tbl 250.122 says I could use a #6 ground from disconnect to panel, right? right But the grounding electrode conductor in Tbl 250.66 requires a #4, so it actually has to be larger than the service panel ground.wrong The GEC is landed at the main disconnect where you bonded the 3/0 neutral from the meter. 2) The plans call for the water pipe ground, ground rod, and building steel to come from the outside disconnect not the panel. It will be a lot easier to come from the panel, is this not the same thing? Instead of feeding through the disconnect and through the panel to building steel.I also think I will take the ground rod ground wire from the meter can.NO 3)The panel is bolted to the steel structure with 3/8x4" bolts, is this not sufficient enough ground or do I need to run a wire from the panel to building steel.This is not the same a s the GEC system. Seems like a useless thing to do? The panel is bonded and bolted already. Will this meet code?NO All feed back on this topic will be appreciated, I have to go back tomorrow. I need to make sure I am doing this right. Thanks. 4) Instead of just running a bare ground to ground rod exposed, should I install it in conduit? Never done that but may look better.If you do, use PVC.