Electrical Machines Which of the following methods of speed control is not affected through stator side? Change of rotor resistance. Change of number of pole. Change of supply frequency. Change of supply voltage. Change of rotor resistance. Change of number of pole. Change of supply frequency. Change of supply voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A generator may loose residual magnetism due to vibrations. heating. over excitation. any of these. vibrations. heating. over excitation. any of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines High inrush of current during a starting of DC motor can efficiently be restricted to a safer value by increasing the _________________ resistance. shunt field both A and B armature circuit none of above shunt field both A and B armature circuit none of above ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following speed control of DC motor the speed obtained is below than the rated speed? Armature voltage control. Any of above. Armature circuit resistance control. Field resistance control. Armature voltage control. Any of above. Armature circuit resistance control. Field resistance control. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following induction motor has maximum speed? 6 pole. 4 pole. 2 pole. 8 pole. 6 pole. 4 pole. 2 pole. 8 pole. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements about commutating poles which are fitted on most large dc Shunt motors: 1. The commutating poles are placed in the geometric neutral plane and their number is usually Equal to the number of main poles 2. The winding on the commutating poles is connected in series with the shunt-field winding on the main poles 3. The polarity of the commutating pole must be that of the next pole further ahead 4. The commutating poles neutralize the reactance voltage produced in the coil undergoing Commutation. Of these statements, 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 3 are correct 1, 2 and 4 are correct 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 3 are correct 1, 2 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP