Electrical Machines If field current is decreased in shunt dc motor, the speed of the motor increases. remains same. decreases. None of these increases. remains same. decreases. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Hunting in a synchronous motor takes place when supply voltage fluctuates. when power factor is unity. when load varies. motor is under loaded. when supply voltage fluctuates. when power factor is unity. when load varies. motor is under loaded. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature resistance control method is also called as-----------? constant current control constant torque control constant voltage control constant power control constant current control constant torque control constant voltage control constant power control ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The following statements relate to compensating winding (CW) and interpole winding (IW) of a dc machine : 1. CW neutralizes the armature reaction under a pole pitch 2. IW is connected in series with armature circuit 3. IW produces mmf in the commutating zone only 4. CWmmf is directed along the brush axis 5. Mmf produced by IW is equal to armature mmf From these, the correct statements are 2, 3, 4 1, 2, 3, 4 and 5 1, 3, 4, 5 2, 3, 4, 5 2, 3, 4 1, 2, 3, 4 and 5 1, 3, 4, 5 2, 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If in a sub – station there is one 132 / 33 kV transformer whose secondary is connected with primary of one 33 / 11 kV transformer, the total transformation ratio of the sub – station will be, 3. 7. 12. 4. 3. 7. 12. 4. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Hysteresis loss will depends on f² f1.6 f f³ f² f1.6 f f³ ANSWER DOWNLOAD EXAMIANS APP
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