200 amp sub panel from 200 amp main (seperate building)

[kwired]

I think he is talking about the OP notion of putting ground rods at each corner of the building. I don't see any reason for that either. A bond to the building steel at one spot should be enough.

Building steel needs to be in contact with earth for at least 10 feet or it is not a grounding electrode, and other electrodes must be used. So a steel truss constructed building is going to depend on just how the truss attaches to the foundation. Just anchors in concrete and no ties to any CEE qualifying rebar or anything does not make the steel frame a GEC.

That said, even if it doesn't qualify as a GEC it may still have less resistance to earth than a ground rod.

 

[ActionDave]

Building steel needs to be in contact with earth for at least 10 feet or it is not a grounding electrode, and other electrodes must be used. So a steel truss constructed building is going to depend on just how the truss attaches to the foundation. Just anchors in concrete and no ties to any CEE qualifying rebar or anything does not make the steel frame a GEC.

That said, even if it doesn't qualify as a GEC it may still have less resistance to earth than a ground rod.

Nobody is saying that you don't need a GEC. At least I'm not and I don't think Charlie was either. That was always a given. Whether the building steel counts toward a grounding electrode or not it needs to be bonded but it does not need to be earthed at each column. The OP has since come back and said he wants extra earthing and that is fine, it's his place.

 

[readydave8]

Charlieb


Most service cables don't include a grounding conductor. So I would have to buy a seperate wire. Would it have to be insulated or can it be directly buried bare cooper?

This was the case around here years ago, now 4/wire is readily available.