Referring to commercial generators, usually 80kW and larger. Solid neutral. Once the pad has been formed I usually drive a couple of ground rods, one outside the pad and one inside the pad to come up inside the generator enclosure. I connect them with a length of #2 bare CU which I also bond to the wire mesh in the pad. Once the generator is installed I connect the ground rod to the frame with another piece of #2. Of course, I also run an EGC with my generator load conductors. It was shown this way on a drawing once, and this is the way I always do it.
My question is this : Is this the correct, code compliant way to do it, or is it overkill? Again, this is a solid neutral so it is not a seperatly derived system (or is it?)
The reason I ask is because we are currently doing an install where we have some serious concerns about what may be running below grade underneath the pad location. The utilities enter the building very close by. Too close for comfort, as mark-outs are not always reliable. I really don't want to drive a ground rod if I don't have to.
Smoke comes out of my ears when I read article 250. Please help.
Thanks.
My question is this : Is this the correct, code compliant way to do it, or is it overkill? Again, this is a solid neutral so it is not a seperatly derived system (or is it?)
The reason I ask is because we are currently doing an install where we have some serious concerns about what may be running below grade underneath the pad location. The utilities enter the building very close by. Too close for comfort, as mark-outs are not always reliable. I really don't want to drive a ground rod if I don't have to.
Smoke comes out of my ears when I read article 250. Please help.
Thanks.