Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3 ,5 1, 2, 3 2, 3, 4 2, 3, 4, 5 2, 3 ,5 1, 2, 3 2, 3, 4 2, 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor is, in general analogous to None of these two winding transformer with secondary open circuited. two winding transformer with secondary short circuited. auto transformer. None of these two winding transformer with secondary open circuited. two winding transformer with secondary short circuited. auto transformer. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two 3-phase AC generators are such that one has twice the linear dimensions of the other. The field windings of each are excited to give identical sinusoidal air-gap flux density waveform. Both have the same number of stator slots and identical winding patterns. The conductor/slot in a big generator is K times that of the smaller one. The value of K to get equal no load voltage at same frequency is 1/4. 8. 1/2. 4. 1/4. 8. 1/2. 4. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, the ripples in the direct emf generated are reduced by employing graphite brushes. carbon brushes. commutator with large number of segments. equalizer rings. graphite brushes. carbon brushes. commutator with large number of segments. equalizer rings. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a three phase star - delta transformer, what is the angle difference between primary and secondary phase voltages? Delta side lags by -30°. Star side leads by 30°. Delta side leads by 30°. Star side lags by -30°. Delta side lags by -30°. Star side leads by 30°. Delta side leads by 30°. Star side lags by -30°. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Field weakening control method is used for the _________ ? both A and B below rated speed None of these above rated speed both A and B below rated speed None of these above rated speed ANSWER DOWNLOAD EXAMIANS APP
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