Transformers In case of 3-phase induction motors, plugging means pulling the motor directly on line without a starter locking of rotor due to harmonics interchanging two supply phases for quick stopping starting the motor on load which is more than the rated load pulling the motor directly on line without a starter locking of rotor due to harmonics interchanging two supply phases for quick stopping starting the motor on load which is more than the rated load ANSWER DOWNLOAD EXAMIANS APP
Transformers Short circuit test on transformers is conducted to determine eddy current losses hysteresis losses core losses copper losses eddy current losses hysteresis losses core losses copper losses ANSWER DOWNLOAD EXAMIANS APP
Transformers When the turns ratio of a transformer is 20 and the primary ac voltage is 12 V, the secondary voltage is 240 V 2,400 V 120 V 12 V 240 V 2,400 V 120 V 12 V ANSWER DOWNLOAD EXAMIANS APP
Transformers Leakage flux in a transformer occurs because Air is not a good magnetic insulator Transformer is not an efficient device Iron core has high permeability Applied voltage is sinusoidal Air is not a good magnetic insulator Transformer is not an efficient device Iron core has high permeability Applied voltage is sinusoidal ANSWER DOWNLOAD EXAMIANS APP
Transformers Which of the following is the main advantage of an auto-transformer over a two winding transformer? Saving in winding material Hysteresis losses are reduced Copper losses are negligible Eddy losses are totally eliminated Saving in winding material Hysteresis losses are reduced Copper losses are negligible Eddy losses are totally eliminated ANSWER DOWNLOAD EXAMIANS APP
Transformers The no load ratio of a 50 Hz single phase transformer is 6000/250 V. The maximum flux in the core is 0.06 Wb. What is the number of primary turns? 350 900 210 450 350 900 210 450 ANSWER DOWNLOAD EXAMIANS APP
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