Electrical Machines A DC Shunt Motor having shunt field resistance of 250 Ω and armature resistance of 0.5 Ω is connected to 250 V supply and load current of 21 A. What is the back emf generated ? 230 V. 210 V 150 V. 240 V. 230 V. 210 V 150 V. 240 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 400 V, 50 Hz, 30 Hp, three phase IM is drawing 50 A current at 0.8 p.f lagging. The stator and rotor copper losses are 1.5 KW and 900 W respectively. The friction and windage losses are 1050 W and core losses are 1200 W. The air gap power of the motor will be 24.11 kW. 23.06 kW. 26.21 kW. 25 kW. 24.11 kW. 23.06 kW. 26.21 kW. 25 kW. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC Motor is driving a constant load torque having armature resistance of 0.25 Ω and armature current of 60 A having connected to a voltage of 230 V. Now a resistance of 1 ohm is added into the armature circuit. The ratio of their speed will be 0.62. 0.72. 1.24. 0.25. 0.62. 0.72. 1.24. 0.25. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt generator has full-load voltage regulation of 10% at rated speed of 1000 rpm. If it is now driven at 1250 rpm, then its voltage regulation at full load would remain unchanged be more than 10% be less than 10% be 12.5% remain unchanged be more than 10% be less than 10% be 12.5% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of DC shunt motor if load is reduced The speed will increase abruptly. The speed will remains almost constant. The speed will increase in proportion to reduction in load. DC Shunt Motor The speed will increase abruptly. The speed will remains almost constant. The speed will increase in proportion to reduction in load. DC Shunt Motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The sparking at the the brushes, in a DC machines is due to high resistance of carbon brushes. presence of commutator. reactance voltage. armature reaction. high resistance of carbon brushes. presence of commutator. reactance voltage. armature reaction. ANSWER DOWNLOAD EXAMIANS APP