A motor control center has three induction motors each rated at 40 HP and 480 V and four induction motors each rated at 30 HP and 480 V. Each 40 HP motor has an efficiency of 0.92 , 1772 rpm, and a power factor of 0.85. Each 30 HP motor has an efficiency of 0.90, and a power factor of 0.90, a nameplate rating of 30 A, a service factor of 1.15 , and a FVR controller.

(a) Determine the number of poles, the slip (%), and the torque delivered by each 40 HP motor.

(b) Size the branch circuit for each 30 HP motor if the source, controller, and motor are all out of sight of each other. Each motor is protected by non-time-delay fuse.

(c) Size the main feeder (conductor and conduit) as well as the non-time-delay fuse and associated switch for the motor control center