Electrical Machines What is/are the necessary conditions for parallel operation of alternators? Terminal voltage is same Speed of alternators should be same Both 1and 2 Frequency should be same Terminal voltage is same Speed of alternators should be same Both 1and 2 Frequency should be same ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In large sized DC machines the compensating windings are provided to reduce eddy current losses by providing local short circuits. compensate for the decrease in speed due to increase of load. neutralize voltage induced in coil due to fluctuation of l None of these reduce eddy current losses by providing local short circuits. compensate for the decrease in speed due to increase of load. neutralize voltage induced in coil due to fluctuation of l None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the back emf in DC motor vanishes suddenly the motor will run at very high speed. burn. run at very low speed. start haunting. run at very high speed. burn. run at very low speed. start haunting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature of DC machine is made of insulating material. non-ferrous material. silicon steel. conducting material. insulating material. non-ferrous material. silicon steel. conducting material. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motors has negative speed regulation? Differential compound motors. Series motors. Shunt motors. Both B and C. Differential compound motors. Series motors. Shunt motors. Both B and C. ANSWER DOWNLOAD EXAMIANS APP