I am installing a sub panel in a metal garage for a customer. feed to the panel has Ground conductor from main pnl. The metal building is on concrete slab. Do we still need a rod? if so one or two? Does 250.52.A.2.1 allow this structure to be used as ground electrode instead?
metal garage gec
- Thread starter shelco
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paul
Senior Member
- Location
- Snohomish, WA
If I understand correctly, you have your two hots, neutral and a ground. If so, then pound one ground rod and tie it to the ground bar in the panel. Bring all your other grounds, as in building steel and piping, back to your ground bar.
- Location
- Bremerton, Washington
- Occupation
- Master Electrician
You need a grounding electrode system. It can be a CEE per 350.52(A)(3) or grounding electrodes. If the resistance is less than 25 ohms one ground rod will suffice. If not drive two and you are done.
If the metal structure meets the requirements in 250.52(A)(2) then it can be the grounding electrode.
While the 2005 NEC allows the grounded conductor to serve in place of an EGC this is not recommended. If you are in Washington State its not been allowed for 3 years.
If the metal structure meets the requirements in 250.52(A)(2) then it can be the grounding electrode.
While the 2005 NEC allows the grounded conductor to serve in place of an EGC this is not recommended. If you are in Washington State its not been allowed for 3 years.
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