Electrical Machines A 4-pole DC generator runs at 1500 rpm. The frequency of current in the armature winding is: 25 Hz. 100 Hz. Zero Hz. 50 Hz. 25 Hz. 100 Hz. Zero Hz. 50 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchorous generator connected to an infinite bus is over excited. Considering only the reactive power from the point view of the system the machine acts as A resistor. A capacitor. None of these. an inductor. A resistor. A capacitor. None of these. an inductor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generators, the cause of rapid brush wear may be any of above. severe sparking. imperfect contact. rough commutator surface. any of above. severe sparking. imperfect contact. rough commutator surface. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machines, the interpoles are provided 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. to counteract the reactance voltage and the cross-magnetizi ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 1, 2 and 3 1, 2, 3 and 4 1, 3 3 only 1, 2 and 3 1, 2, 3 and 4 1, 3 3 only ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In electric locomotive which of the following motor are used ? Synchronous motor. Shunt motor. Separately compound motor. DC series motor. Synchronous motor. Shunt motor. Separately compound motor. DC series motor. ANSWER DOWNLOAD EXAMIANS APP
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