I have been asked to check a ground electrode conductor size. From the utility, there are parallel 3/0 conductors to the MCC. (Two 3/0 per phase, Two parallel conduits, each with the 3 phases and a #4 ground)
The two #4 grounds from the utility terminate on the MCC ground buss. So far so good. Now, the grounding electrode conductor from the MCC to the ground electrode (the customers ground electrode) is one #2 conductor. From table 250.66 it appears that the grounding electrode conductor should be two #4's. Am I right?
Thanks for any help