Q: What color coding does the NEC 2008 require for the circuit or the feeder conductor?
A: I hear this the time that in residential you have to have Blk, Red & white or in commercial you can’t have two black conductors feeding a single phase load.
Truth of the matter is, besides the requirement for the ungrounded (Neutral) conductor stated in 200.6 and the requirements for the EGC (equipment grounding conductor) in section 250.118, generally there are no requirements for the ungrounded conductor to be a certain color code. However, the electrical industry has adopted the following as a field practice:
Brown, Orange, Yellow, Gray for 480V-277V
Black, Red, Blue, White for 208V-120V
On a second note, the only requirement per NEC section 110.15 is the color orange that is reserved for the high leg in a 3 phase four wire delta system where the ungrounded conductor is available.
