Electrical Machines Sparkless commutation can be achieved by employing inter poles. any one or more of the above methods. high resistance carbon brushes. compensating winding. inter poles. any one or more of the above methods. high resistance carbon brushes. compensating winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, alternator has generated emf per phase of 230 V with 10% 3rd harmonic and 6% 5th harmonic content. Calculate rms line voltage for star connection. 399 V. 50 V. 230.2 V. 100 V. 399 V. 50 V. 230.2 V. 100 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A short circuit test on a transformer gives copper loss at half load. copper loss at full load. copper loss at any load. copper loss at over load. copper loss at half load. copper loss at full load. copper loss at any load. copper loss at over load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following factors improve commutation in a dc machine ? 1. High contact resistance of brushes 2. High inductance of the coils undergoing commutation 3. Shifting of brushes in the direction of rotation for a generator and in the opposite direction For a motor 4. Narrow width for the commutation bars Select the correct answer using the codes given below : Codes : 1, 2 and 4 2, 3 and 4 1 and 3 1, 2, and 3 1, 2 and 4 2, 3 and 4 1 and 3 1, 2, and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A series motor is efficiently suitable for constant speed operation. none of these. low starting torque operation. high starting torque operation. constant speed operation. none of these. low starting torque operation. high starting torque operation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 2 pole, 12 slot synchronous machine is operating at synchronous speed. Find the slot angle? 20° 30° 18° 60° 20° 30° 18° 60° ANSWER DOWNLOAD EXAMIANS APP
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