Electrical Machines A dc shunt generator, when commissioned after a major repair of the field system, failed to build Up voltage. It was because field resistance was higher than critical resistance field winding was wrongly connected field system lost residual magnetism there was a break in the armature circuit field resistance was higher than critical resistance field winding was wrongly connected field system lost residual magnetism there was a break in the armature circuit ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 230 V dc series generator is driven at its rated speed. The no-load voltage across its armature terminals would be 230 V 6 V somewhat more than 230 V somewhat less than 230 V 230 V 6 V somewhat more than 230 V somewhat less than 230 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor is running at rated speed without any additional resistance in series. If an additional resistance is placedin series, the speed of motor Remains unchanged. Oscillates around the rated speed. Increases. Decreases. Remains unchanged. Oscillates around the rated speed. Increases. Decreases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In large sized DC machines the compensating windings are provided to None of these neutralize voltage induced in coil due to fluctuation of l reduce eddy current losses by providing local short circuits. compensate for the decrease in speed due to increase of load. None of these neutralize voltage induced in coil due to fluctuation of l reduce eddy current losses by providing local short circuits. compensate for the decrease in speed due to increase of load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a loaded DC generator, if the brushes are given a shift from the interpolar axis in the direction of rotation, then the commutation will improve with rise in terminal voltage. deteriorate with rise in terminal voltage. deteriorate with fall of terminal voltage. improve with fall of terminal voltage. improve with rise in terminal voltage. deteriorate with rise in terminal voltage. deteriorate with fall of terminal voltage. improve with fall of terminal voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A voltmeter gives 120 oscillations per minute when connected to the rotor of an induction motor. The frequency is 50Hz. The slip of the motor is 5% 4% 25% 2% 5% 4% 25% 2% ANSWER DOWNLOAD EXAMIANS APP