Electrical Machines The compensating winding in a DC machine is located in armature slots for compensation of the armature reaction. is located on commutating poles for improving commutation. is located on pole shoes to avoid the sparking at the brushes. is located on pole shoes for avoiding the flashover at the commutator. is located in armature slots for compensation of the armature reaction. is located on commutating poles for improving commutation. is located on pole shoes to avoid the sparking at the brushes. is located on pole shoes for avoiding the flashover at the commutator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following methods are used to control the speed of DC motors is supply voltage control armature circuit resistance control All of these field current control supply voltage control armature circuit resistance control All of these field current control ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ slip ring motor has double cage rotor. wound rotor. short-circuited rotor. any of the above. double cage rotor. wound rotor. short-circuited rotor. any of the above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For successful parallel operation of two single phase transformers, the most essential condition is that their KVA ratings are equal percentage impedances are equal polarities are properly connected turn- ratios are exactly equal KVA ratings are equal percentage impedances are equal polarities are properly connected turn- ratios are exactly equal ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc machine, 1. physically, the brush axis is along the direct axis 2. physically, the brush axis is along the interpolar axis 3. schematically, the brush axis is along the direct axis 4. schematically, the brush axis is along the quadrature axis 5. armaturemmf is directed along the brush axis From these, the correct statements are 1 , 3, 5 2, 4, 5 2, 3, 5 1, 4,5 1 , 3, 5 2, 4, 5 2, 3, 5 1, 4,5 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, 3 1, 2, 3 and 4 3 only 1, 2 and 3 1, 3 1, 2, 3 and 4 3 only ANSWER DOWNLOAD EXAMIANS APP