Electrical Machines Maximum allowable tan - delta (tanδ) of dielectric dispassion factor of power transformer insulating oil is generally taken as 3 at 90°C. 2 at 90°C. 1 at 90°C. 0.5 at 90°C. 3 at 90°C. 2 at 90°C. 1 at 90°C. 0.5 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a three phase star - delta transformer, what is the angle difference between primary and secondary phase voltages? Star side leads by 30°. Delta side leads by 30°. Delta side lags by -30°. Star side lags by -30°. Star side leads by 30°. Delta side leads by 30°. Delta side lags by -30°. Star side lags by -30°. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In 3 - Φ induction motor some times copper bars are placed deep in the rotor to improve efficiency. improve starting torque. improve power factor. reduce copper loss. improve efficiency. improve starting torque. improve power factor. reduce copper loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole dynamo with wave wound armature has 51 slots contains 20 conductors in each slot. If induced emf 357 Volts and speed is 8500 rpm, flux per pole will be 1.2 mWb. 3.5 mWb. 2.7 mWb. 1.4 mWb. 1.2 mWb. 3.5 mWb. 2.7 mWb. 1.4 mWb. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Why are capacitors used with large AC induction motor? Improve power level. Improve power factor. Improve voltage level. Improve current level. Improve power level. Improve power factor. Improve voltage level. Improve current level. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Series booster is a series wound DC generator. shunt wound DC generator. permanent magnet DC generator. separately excited DC generator. series wound DC generator. shunt wound DC generator. permanent magnet DC generator. separately excited DC generator. ANSWER DOWNLOAD EXAMIANS APP
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