Electrical Machines A 3 - Φ, 6 pole, 50 Hz IM has a rotor speed of 987 rpm find rotor frequency? 60 Hz. 0.65 Hz. 0.75 Hz. 0.70 Hz. 60 Hz. 0.65 Hz. 0.75 Hz. 0.70 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor when started on no load does not accelerate up to full speed but runs at 1/7th of the rated speed. The motor is said to be locking. plugging. cogging. crawling. locking. plugging. cogging. crawling. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Satisfactory commutation of DC machine requires All of these brushes should smoothly run in the holders. brushes should be of proper grade and size. smooth, concentric commutator properly undercut. All of these brushes should smoothly run in the holders. brushes should be of proper grade and size. smooth, concentric commutator properly undercut. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To control the speed of an induction motor, the supply frequency is reduced by 10%. For the same magnetizing current to remain constant, the supply voltage must be reduced by 20% increased by 20% increased by 10% reduced by 10% reduced by 20% increased by 20% increased by 10% reduced by 10% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3- phase synchronous motor can operate over a wide range of power factors i.e. from lagging to leading power factor. This is achieved by changing the load. changing the field excitation. varying the speed. varying the applied voltage. changing the load. changing the field excitation. varying the speed. varying the applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 250 volt dc series motor having an armature resistance of 0.2 Ω takes a load current of 60 A. What will be the torque produced at the shaft of the motor? Consider brush drop of 1V. 133.22 N-m 234.76 N-m. 266.20 N-m. can not be determined. 133.22 N-m 234.76 N-m. 266.20 N-m. can not be determined. ANSWER DOWNLOAD EXAMIANS APP