scrypps
Member
- Location
- United States
Situation: Lighting Control. A single 20a circuit feeds 8 lighting loads in a room. The contractor ran 8 hots and 8 neutrals for a total of 16 current carrying conductors in a 20' run of 1-1/2" emt from the control module to a j-box in the ceiling where lighting loads are. According to 310.15(b)(3), these should be de-rated by 50%.
My issue is that per 310.15, I can install 4 fully loaded 20a circuits and have 80 amps of power going through a conduit and the code is fine with it. In this case, we have 16 conductors carrying a maximum of 7 amps, and the code is not ok with that if the conductors are 12awg. Furthermore, if this wasn't lighting control, there would just be a hot and a neutral running to a box with 8 switches in it.
I'm inclined to think of it as not a big deal, I just can't imagine a heat damage situation occurring.
As a though experiment. What if I had one 20a circuit serving a permanently connected load of 7amps and just for the heck of it, I decided to parallel my #12 conductors in a long raceway from box to box, so the run had 16 pretty conductors spliced together from end to end. Would this be a violation of 310.15(B)(3) and would the intent of that section be met if this were considered a violation?
My issue is that per 310.15, I can install 4 fully loaded 20a circuits and have 80 amps of power going through a conduit and the code is fine with it. In this case, we have 16 conductors carrying a maximum of 7 amps, and the code is not ok with that if the conductors are 12awg. Furthermore, if this wasn't lighting control, there would just be a hot and a neutral running to a box with 8 switches in it.
I'm inclined to think of it as not a big deal, I just can't imagine a heat damage situation occurring.
As a though experiment. What if I had one 20a circuit serving a permanently connected load of 7amps and just for the heck of it, I decided to parallel my #12 conductors in a long raceway from box to box, so the run had 16 pretty conductors spliced together from end to end. Would this be a violation of 310.15(B)(3) and would the intent of that section be met if this were considered a violation?