DieselShip's Online Content Library

Q3. A 6 pole, three phase squirrel cage induction motor runs on a 415 V, 60 Hz supply. It draws a line current of 85 A at a power factor of 0.75 lag. The shaft speed is 19 revs/sec. If the iron losses are 2 KW, the stator copper loss is 1 KW and the rotational losses (windage and friction) are 1.5 KW, calculate EACH of the following:

(a) The slip as a per unit value;

(b) The rotor copper loss;

(c) The shaft output power;

(d) The efficiency.