Synchronous Motors In case one phase of a three-phase synchronous motor is short-circuited the motor will not start run with excessive vibrations take less than the rated load run at 2/3 of synchronous speed not start run with excessive vibrations take less than the rated load run at 2/3 of synchronous speed ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors In a synchronous motor, the magnitude of stator back emf depends on _____ Dc excitation only Both the speed and rotor flux Load on the motor Speed of the rotor Dc excitation only Both the speed and rotor flux Load on the motor Speed of the rotor ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The pull out torque of a practical synchronous motor will occur when the torque angle is about _____ 30° 75° 45° 0° 30° 75° 45° 0° ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors When pull-out torque occurs in a synchronous motor, the poles of the rotor are _______ None of the listed here Mid way between N and S poles of stator 45° (electrical) behind stator poles Coincident with statorbpoles None of the listed here Mid way between N and S poles of stator 45° (electrical) behind stator poles Coincident with statorbpoles ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors If the field of a synchronous motor is underexcited, the power factor will be unity zero lagging leading unity zero lagging leading ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors Hunting in a synchronous motor cannot be due to variable load windage friction variable frequency variable supply voltage variable load windage friction variable frequency variable supply voltage ANSWER DOWNLOAD EXAMIANS APP