Electrical Machines In DC machines, the interpoles are provided to make commutation spark less. to counteract demagnetizing effect of armature mmf in commutating zone. both (B) and (C). to counteract the reactance voltage and the cross-magnetizi to make commutation spark less. to counteract demagnetizing effect of armature mmf in commutating zone. both (B) and (C). to counteract the reactance voltage and the cross-magnetizi ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, the field system has to be provided on stator unlike synchronous machines Where in it could be on any member, because dc machines are comparatively low rating machines. it reduces field structure iron losses it gives more uniform air-gap flux distribution commutator action is not possible otherwise dc machines are comparatively low rating machines. it reduces field structure iron losses it gives more uniform air-gap flux distribution commutator action is not possible otherwise ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What will be the e.m.f. generated by a 4 pole lap connected DC Generator rotating at 1500 r.p.m.? Its flux per pole is 0.4 mWb and total no of armature conductors is 1000. 30 volts. 20 volts. 40 volts. 10 volts. 30 volts. 20 volts. 40 volts. 10 volts. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are the advantages of carbon brush over the copper brush? They are not hard as copper brush They are self lubricating in nature In case of any sparking they will be less damaged than copper brushes All of these They are not hard as copper brush They are self lubricating in nature In case of any sparking they will be less damaged than copper brushes All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc motors, under leading pole tips flux density will--------? either increase or decrease increase None of these decrease either increase or decrease increase None of these decrease ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The factors that are responsible for decrease in terminal voltage of a shunt generator are armature resistance, inter poles, armature. armature resistance, effect of armature reaction. armature resistance, effect of armature reaction. reduction in field current, effect of armature reaction, armature. armature resistance, inter poles, armature. armature resistance, effect of armature reaction. armature resistance, effect of armature reaction. reduction in field current, effect of armature reaction, armature. ANSWER DOWNLOAD EXAMIANS APP