Electrical Machines In a DC generator sparking between brushes and commutator surface may be due to under commutation. any of the above. too rapid reversal of current. over commutation. under commutation. any of the above. too rapid reversal of current. over commutation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor the 7th harmonic torque may make the motor rotate at (1 / 7)th synchronous speed. This is called cogging. crawling. resonance. harmonics. cogging. crawling. resonance. harmonics. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Diverters are used only in series motors shunt motors either of these None of these series motors shunt motors either of these None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 25 Hz 0 Hz 100 Hz 50 Hz 25 Hz 0 Hz 100 Hz 50 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum allowable moisture content of power transformer insulating oil is generally taken as 25 ppm. 20 ppm. 35 ppm. 45 ppm. 25 ppm. 20 ppm. 35 ppm. 45 ppm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What does happen if tripled harmonics given to induction motor? Nothing will happen. Will results in open circuit. Fail to start. Will results in short circuit. Nothing will happen. Will results in open circuit. Fail to start. Will results in short circuit. ANSWER DOWNLOAD EXAMIANS APP