Sorry in advance as I know this has been beat to death, but I have multiple instances of small 480-208Y/120V xfmrs in a concrete/wood fame industrial building with nothing to ground to (no steel or water pipe). Inspector wants a GEC routed back to the service rather than driving a local rod per 250.30 (7) Exception #1 and 250.52 (A)(5). The service is up to 300ft away in some cases. Do you agree that this is the best solution? Since the CMP can't agree on the dual use (EGC/GEC) of an upsized feeder EGC I don't plan to pursue that avenue.
SDS Xfmr Gnding Again
- Thread starter W6SJK
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Recent threads have changed my opinions on this. I used to put a lot of stock in "the same area" wording, but now realize the premises metal water pipe electrode takes preference despite it not being "near".
In your situation, if there is no structural steel or metal water electrode on the premises, then I would think any of the electrodes in 210.52 would be installed. If the service does not have a structural metal or water pipe electrode I see no reason of routing your GEC there.
In your situation, if there is no structural steel or metal water electrode on the premises, then I would think any of the electrodes in 210.52 would be installed. If the service does not have a structural metal or water pipe electrode I see no reason of routing your GEC there.
- Location
- Bremerton, Washington
- Occupation
- Master Electrician
I don't see where 250.30 would require a GEC back the building electrical ground. 300 ft is not in the "area". But if the transformers were able to have there grounding daisy chained one to the next, and to the service that might be one solution.
Tom,
This was discussed in the earlier thread: http://forums.mikeholt.com/showthread.php?t=118935&highlight=transformer
Do you agree that if the premises has a metal underground water pipe that qualifies as a grounding electrode and no effectively grounded building steel the GEC for the SDS would be required to run back to the water pipe within 5 ft of entry to the building ? (unless the exception to 250.52(A)(1) was in effect),
This was discussed in the earlier thread: http://forums.mikeholt.com/showthread.php?t=118935&highlight=transformer
Do you agree that if the premises has a metal underground water pipe that qualifies as a grounding electrode and no effectively grounded building steel the GEC for the SDS would be required to run back to the water pipe within 5 ft of entry to the building ? (unless the exception to 250.52(A)(1) was in effect),
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