For the motor of Prob P9.27
(a) calculate the starting torque when rated voltage is applied to the stator.
(b) calculate the slip at which the motor develops maximum torque and the value of this torque.
(c) what is the output torque and power in part (b)?
Prob P9.27:
A squirrel-cage induction motor is rated 25 kW, 440 V, 3-phase, 50 Hz. On full-load it draws 28.7 kW with line current 50 A and runs at 720 rpm. Calculate
(a) the slip,
(b) the power factor, and
(c) the efficiency.