Hypothetical Motor and Lighting Cir

[Dennis Alwon]

240.4 Protection of Conductors. Conductors, other than flexible cords, flexible cables, and fixture wires, shall be protected against overcurrent in accordance with their ampacities specified in 310.15, unless otherwise permitted or required in 240.4(A) through (G).

To save space (G) includes motors.

I think we can all agree that a 10 amp single phase 120v motor can be run on a 14 gauge wire and installed with a 20 amp overcurrent protective device. Now suppose we want to add some other things to this circuit. Art. 210.3, stated below, recognizes that this circuit is a 20 amp circuit.

210.3 Rating. Branch circuits recognized by this article shall be rated in accordance with the maximum permitted ampere rating or setting of the overcurrent device.

If it is a 20 amp circuit with a 10 amp load then art. 210.23, stated below, allows lighting and receptacles to be on the circuit.

210.23(A)(2) Utilization Equipment Fastened in Place. The total rating of utilization equipment fastened in place, other than luminaires, shall not exceed 50 percent of the branch circuit ampere rating where lighting units, cord-and-plug connected utilization equipment not fastened in place, or both, are also supplied.

So can I add 20 amp wire to the lighting part and still keep the circuit at 20 amps or does it have to go back to 15 amps? Remember the wire to the pump from the panel is 14 gauge.

I realize it sounds and feels wrong but what article will this install violate?

 

[Dennis Alwon]

I think I answered my own question. I suspect 240.4 disallows it.