Electrical Machines A 3-phase, 2 pole, 12 slot synchronous machine is operating at synchronous speed. Find the slot angle? 60° 20° 30° 18° 60° 20° 30° 18° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, 1. reactance voltage is proportional to armature current 2.reactance voltage is proportional to core length 3.reactance voltage is due to self-flux of the coil undergoing commutation 4. armature-cross flux is neutralized by interpolar flux 5. interpolarmmf is more than armature mmf in the interpolar zone From these, the correct answer is 1, 2, 5 1, 2, 3, 4 2, 3, 4 1, 3, 5 1, 2, 5 1, 2, 3, 4 2, 3, 4 1, 3, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The low voltage winding of a 400/230 V single phase 50 Hz transformer is to be connected to keep the magnetization current at the same level in both the cases the voltage at 25 Hz should be 460 V 65 V 115 V 230 V 460 V 65 V 115 V 230 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a single phase capacitor start induction motor which of the following is valid? None of these. Rotation can be changed by reversing main winding terminals. Rotation can be changed by interchanging supply terminals. Direction of rotation cannot be changed. None of these. Rotation can be changed by reversing main winding terminals. Rotation can be changed by interchanging supply terminals. Direction of rotation cannot be changed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In the 3-phase induction motor, the resultant flux is of a constant nature and is equal to φm, where φm is the maximum flux due to any phase 1/2 times maximum value of flux due to any phase 3/2 times maximum value of flux due to any phase 3 times maximum value of flux due to any phase equal to φm, where φm is the maximum flux due to any phase 1/2 times maximum value of flux due to any phase 3/2 times maximum value of flux due to any phase 3 times maximum value of flux due to any phase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machines, the interpoles are provided to make commutation spark less. to counteract the reactance voltage and the cross-magnetizi both (B) and (C). to counteract demagnetizing effect of armature mmf in commutating zone. to make commutation spark less. to counteract the reactance voltage and the cross-magnetizi both (B) and (C). to counteract demagnetizing effect of armature mmf in commutating zone. ANSWER DOWNLOAD EXAMIANS APP