Electrical Machines What is/are the necessary conditions for parallel operation of alternators? Both 1and 2 Speed of alternators should be same Terminal voltage is same Frequency should be same Both 1and 2 Speed of alternators should be same Terminal voltage is same Frequency should be same ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The oscillation in a synchronous motor can be damped out by oscillation cannot be damped. providing damper bars in the rotor pole faces. maintaining constant excitation. running the motor on leading power factors. oscillation cannot be damped. providing damper bars in the rotor pole faces. maintaining constant excitation. running the motor on leading power factors. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If peak value of phase mmf is F max , then peak value of the rotating field caused by three phase is (1/2)Fmax. 3Fmax. (3/2)Fmax. Fmax. (1/2)Fmax. 3Fmax. (3/2)Fmax. Fmax. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor is running at rated speed without any additional resistance in series. If an additional resistance is placedin series, the speed of motor Decreases. Increases. Remains unchanged. Oscillates around the rated speed. Decreases. Increases. Remains unchanged. Oscillates around the rated speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor speed of an induction motor is given by Ns = 120f /p × ( 1 - r). Ns = 120f / p × ( 1 - s ). Nr = 120f / p × (1-s). None of these Ns = 120f /p × ( 1 - r). Ns = 120f / p × ( 1 - s ). Nr = 120f / p × (1-s). None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motors has low ratings only? Resistance split phase Capacitor run Shaded pole Capacitor start Resistance split phase Capacitor run Shaded pole Capacitor start ANSWER DOWNLOAD EXAMIANS APP
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