Re: current on a grounding electrode conductor
That is a hard question to answer. Typically less than 1-amp. If you have an extremely low ground electrode system (GES) impedance, and a lot of unbalanced load current on the neutral (grounded circuit conductor) it can approach 1-amp. There will always be some current, if not you have probably got a different problem like a poor connection in the GEC, MBJ, or extremely poor GES.
On the other hand if there is a problem with the neutral conductor (grounded circuit conductor) between the transformer and your service, like poor connections, the GEC current will be high.
Look at the voltage between each phase to the grounded circuit conductor (neutral). It should be balanced or approx the same voltage from each leg to neutral (grounded circuit conductor)
Edit made for Charlie B.
[ October 10, 2003, 01:15 PM: Message edited by: dereckbc ]