Electrical Machines In a 6 pole DC machine, 90 mechanical degrees correspond to which of the following electrical degree? 45. 30. 180. 270. 45. 30. 180. 270. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the efficiency when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 67.5% 82.5% 72.5% 78.5% 67.5% 82.5% 72.5% 78.5% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the reactance voltage when current is changed from -2A to 2A in 4 sec and self inductance is 1H? 2 V 0 V 1 V 4 V 2 V 0 V 1 V 4 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the phase difference between two windings of A.C servomotor ? 90°. 120°. 60°. 30°. 90°. 120°. 60°. 30°. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following represents the operating region of slip in a 1-phase induction motor? 0 < S < 2 0 < S < 1 -1 < S < 1 -2 < S < 2 0 < S < 2 0 < S < 1 -1 < S < 1 -2 < S < 2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machines, the interpoles are provided to counteract the reactance voltage and the cross-magnetizi to make commutation spark less. both (B) and (C). to counteract demagnetizing effect of armature mmf in commutating zone. to counteract the reactance voltage and the cross-magnetizi to make commutation spark less. both (B) and (C). to counteract demagnetizing effect of armature mmf in commutating zone. ANSWER DOWNLOAD EXAMIANS APP
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