Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm. Find the rotor efficiency? 92% 94% 96% 95% 92% 94% 96% 95% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Interpoles in a DC motor must be Shunt excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Demagnetization effects which of the following? reduction in main field flux commutation reduces the terminal voltage both B and C reduction in main field flux commutation reduces the terminal voltage both B and C ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a cumulatively compound DC motor can be controlled by varying Shunt field resistance control. Any of above. Armature resistance control. Armature voltage control. Shunt field resistance control. Any of above. Armature resistance control. Armature voltage control. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To eliminate the 5th harmonic in the induced voltages their respective pitch factor angle should be 18° 30° 72° 36° 18° 30° 72° 36° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following transformer insulating oil generally used in India? Paraffin based insulating oil. Naphtha based insulating oil. Aromatics based insulating oil. Olefin based insulating oil. Paraffin based insulating oil. Naphtha based insulating oil. Aromatics based insulating oil. Olefin based insulating oil. ANSWER DOWNLOAD EXAMIANS APP