How can I get an official interpellation of 250.66(B) as the sole means for grounding for a service over 3/0. From NFPA. This is a 400 amp service sized per 310.15(B)(6). New construction with no other means available per 250.50.
Single family dwelling. I need something official from NFPA.
Single family dwelling. I need something official from NFPA.