New service to existing facility


Considering the price of copper the owner is asking If an existing 3 phase 4 wire distribution board that only serves 3 phase 3 wire motor loads require a neutral conductor in the new feeder serving the board. I would like to reference a code rule rather than his talent for value engineering.


Senior Member
Staff member
There is no NEC requirement that you must take a neutral conductor to a panelboard. This is a design issue. You are required to bring a grounded conductor to the service disconnecting means, but after that the neutral is optional.