Electrical Machines In a star - delta starting of an IM resistance is inserted in the rotor. line voltage is 57.7 % of stator voltage. reduced voltage is applied to the stator. applied voltage per stator phase is 57.7 % of a line volt resistance is inserted in the rotor. line voltage is 57.7 % of stator voltage. reduced voltage is applied to the stator. applied voltage per stator phase is 57.7 % of a line volt ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 4 pole, 50 Hz induction motor 4 % slip, calculate frequency of the rotor emf? 3 Hz. 2 Hz. 10 Hz. 50 Hz. 3 Hz. 2 Hz. 10 Hz. 50 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the magnetization characteristics of a dc generator : 1. It represents the variation of field flux with field current. 2. Variation of open-circuit terminal voltage with field current is independent of speed 3. It is non-linear from zero to rated field current 4. It helps to determine the critical field resistance at a given speed 5. It always starts from the origin Which of these statements are correct ? 3 and 5 2, 3 and 4 1 and 4 1, 2 and 5 3 and 5 2, 3 and 4 1 and 4 1, 2 and 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of 3 - Φ IM, plugging means locking of rotor due to harmonics. pulling the motor directly on line without a rotor. starting the motor on load which is more than the rated load. interchanging two supply phases for quick stopping. locking of rotor due to harmonics. pulling the motor directly on line without a rotor. starting the motor on load which is more than the rated load. interchanging two supply phases for quick stopping. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, if P be the number of poles and N be the rpm of the rotor, then frequency of magnetic reversals will be PN/60. PN/3000. PN/120. PN/2. PN/60. PN/3000. PN/120. PN/2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A series motor is efficiently suitable for none of these. constant speed operation. high starting torque operation. low starting torque operation. none of these. constant speed operation. high starting torque operation. low starting torque operation. ANSWER DOWNLOAD EXAMIANS APP
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