Electrical Machines The rotor speed of an induction motor is given by None of these Ns = 120f /p × ( 1 - r). Nr = 120f / p × (1-s). Ns = 120f / p × ( 1 - s ). None of these Ns = 120f /p × ( 1 - r). Nr = 120f / p × (1-s). Ns = 120f / p × ( 1 - s ). ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Damper winding is used to increase the load current. decrease the load current. both 1 and 2. suppress the hunting. increase the load current. decrease the load current. both 1 and 2. suppress the hunting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC compound motor has only series field winding. only shunt field winding. tertiary winding. both shunt and series field winding. only series field winding. only shunt field winding. tertiary winding. both shunt and series field winding. 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, 2 and 4 are correct 2, 3 and 4 are correct 1, 2 and 3 are correct 1 and 4 are correct 1, 2 and 4 are correct 2, 3 and 4 are correct 1, 2 and 3 are correct 1 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ induction motor draws an current of 50 A from mains when starts by direct switching. If an auto transformer with 60 % tapping is used for starting the current drawn from the mains will be 36. 80. 50. 18. 36. 80. 50. 18. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field connection of a DC Shunt Motor is changed then it will run in opposite direction. motor will not run. it will run in same direction by slowly. it will run in same direction. it will run in opposite direction. motor will not run. it will run in same direction by slowly. it will run in same direction. ANSWER DOWNLOAD EXAMIANS APP