Question

1) A 220V dc motor has an armature resistance of 0.5 Ω. The full load armature current is 20 A. The starting torque of the motor is 880 N-m, Find the full load speed of the motor. (Ans: 2052 r.p.m.)

2) A 220V dc motor developing 25 hp (18.65 kW) runs at a speed of 1000 r.p.m.. Calculate the torque in N-m if the efficiency of the motor is 90%. (Ans: 178 N-m)

Answer 1