This is not a code problem. Its an engineering problem. If the grounding conductor is too long the impedance may cause a delay in the opening of the breaker. The 100 ft is a rule of thumb. To know if there is a problem you would need to caculate the fault current and check the curves for the breaker. How long is the conductor?
250.66 doesn't seem vary silent. it seems to be directly to the point. now I've been doen these service changes for a few years and never had the AHJ call me on the 80 some feet of ground condutor be to long. i just can't see the AHJ call me for something thats not in the code.
Bucketman, I agree with you, as far as the GEC there is no restriction to length as you have said and in fact if the #4 GEC is bare it becomes part of the "Electrode" and the GE's function won't be improved to any great performance level by increasing the conductor size.
With this length of #4 copper in the ground, and if we were talking about a rod, the conductor would probably provide more of a GE than the rod itself.
Bob, the GE and GEC would play no part in the operation of an overcurret device.
[This message has been edited by Roger (edited 03-02-2005).]