We had one of our crews run into a situation yesterday with derating.
Final inspection, a new office in a converted industrial space. The guys had run 7 ckts. in a 3/4" emt. 7 hots, 7 neutrals, one ground, #12 thhn, 20a ocpd.
The state inspector failed them for derating. He said that, "Since this was a single phase service all neutrals are counted as current carrying conductors." These circuits are all general use plugs and lighting. No Non-linear loads, no HID lighting.
My repsonse is WTF??????? This is definitely a new one on me. I consider that conduit to have 7 current carrying conductors per the NEC. Please educate me if I'm wrong.
GJ
