Grounding a transformer

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Electric Slyde Guy

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We just installed a 75kVA transformer inside a building for a commercial business. We drove a ground rod straight into the ground, through the concrete, inside the building to ground the transformer. (we did forget 1 grounding rod, silly me) The inspector didn't like that and asked us to run a ground cable (which would be of much more length, with many more bends) to the a metal part of the building instead. There wasn't really a good spot to ground the transformer to the building with out having to run a long grounding conductor to a metallic part of the building. He did mention the second grounding rod being missing, but didn't ask for the other it to be installed but wanted the the transformer grounded to the building which is going to be much longer grounding conductor. My question is wouldn't it be better to have another ground rod 10ft away, installed and have a shorter grounding conductor than running a long conductor to another section of the building? Was I wrong in assuming this?
Thanks
 
All grounding electrodes for a structure have to be tied together to form one Grounding Electrode System. 250.50

The building steel would be a good place to tie in. 250.68 refers to this.

You cannot just add a single stand alone electrode for the tranny.
 
I agree with Derek, you need to connect the GEC to the building GES. Pounding a rod or two is not an option even if using the building GES means that the GEC will be long.
 
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