Grounding Electrode for Multiple Separately Derived Systems - NEC 250.30A4

[tombrinson]

Our firm commonly uses the method described in NEC 250.30A4 to ground multiple dry type transformers in larger buildings (i.e. schools, large commercial offices) as follows:
From the equipment ground bar in the main switchboard (MSB) we route a 3/0 copper conductor, looped around the building, to ground plates in each electrical room.
The plates are typically 1/4"x4"x12" copper. From the plate to the Xo bar in the transformer a grounding electrode conductor, based on 250.66, is installed using a crimp type connector.

My questions are:
1. Can the 3/0 conductor be "looped" (i.e. terminated with crimp connectors) in and out from room to room? Or does it have to be continuous?
2. Can it routed multiple runs, (i.e. from the MSB to each electrical room) within the same building or does it have to be a continuous loop?

 

[me=mc pulled]

The 3/0 can be "looped" if you follow 250.30(4)(c) at the taps and 250.64(c) for the g e c.Also I see no reason you could not use a seapreate run for each.

 

[Bea]

Question 1 you can terminate from ge to buss on one floor then terminate buss to buss between floors without it be continuous back to ge.
Question 2 is generally ok considering the bussing in most MDP is 2"x 1/4 x the length of gear but IMO Number One would be my perferred method.