As I interpret the NEC, specifically 250-30, in terms of grounding the secondary of a separately derived system, the grounding electrode conductor must terminate at the system ground (XO/neutral) directly from the building ground grid.
1) Is there any provision, or is it even wise to land the grounding electrode conductor on the equipment ground bar in the transformer, then bond XO to the ground bar?
2) While this creates a different path for phase/neutral fault current than directly to building steel, is the path not mechanically sound? What are the implications of such a set up?
I am interested in learning the reason/theory behind bonding XO directly to building steel. Any assistance would be greatly appreciated.
1) Is there any provision, or is it even wise to land the grounding electrode conductor on the equipment ground bar in the transformer, then bond XO to the ground bar?
2) While this creates a different path for phase/neutral fault current than directly to building steel, is the path not mechanically sound? What are the implications of such a set up?
I am interested in learning the reason/theory behind bonding XO directly to building steel. Any assistance would be greatly appreciated.