Electrical Machines An alternator is feeding an infinite busbar. Its prime mover is suddenly shutdown. The alternator will come to stand still. continue to work as alternator but the direction of rotation will reverse. continue to work as synchronous motor with same direction of rotation. start working as induction motor. come to stand still. continue to work as alternator but the direction of rotation will reverse. continue to work as synchronous motor with same direction of rotation. start working as induction motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What will happen if the the supply terminals are reversed in case of a DC shunt motor? The motor will run in reverse direction. The motor will run at its normal speed in the same direction as before. The motor will stop. The motor will run much faster in the same direction. The motor will run in reverse direction. The motor will run at its normal speed in the same direction as before. The motor will stop. The motor will run much faster in the same direction. 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 3 are correct 2, 3 and 4 are correct 1, 2 and 4 are correct 1 and 4 are correct 1, 2 and 3 are correct 2, 3 and 4 are correct 1, 2 and 4 are correct 1 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A compound dc generator is delivering full load current at a terminal voltage of 230 V. Its series-field winding gets short circuited. If its terminal voltage 1. becomes more than 230 V, it is overcompounded generator 2. becomes more than 230 V, it is differentially compounded generator 3. becomes less than 230 V, it is overcompounded generator 4. becomes less than 230 V, it is differentially compounded generator 5. becomes less than 230 V, it is level compounded generator From these, the correct answer is 1, 4, 5 2,3 2, 3, 5 1, 4 1, 4, 5 2,3 2, 3, 5 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of following DC generator will be in a position to build up without any residual magnetism in the field? Series. Separately excited. Shunt. Compound. Series. Separately excited. Shunt. Compound. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cogging and crawling are phenomena associated with the former at a fraction of its rate speed and the latter during starting. any of the above. the former during starting and the latter at a fraction of its rated speed. cage induction machines and they are essentially the same. the former at a fraction of its rate speed and the latter during starting. any of the above. the former during starting and the latter at a fraction of its rated speed. cage induction machines and they are essentially the same. ANSWER DOWNLOAD EXAMIANS APP