Electrical Machines The speed of stator rotating magnetic field (RMF) with respect to rotor is Zero Nr S.Ns Ns Zero Nr S.Ns Ns ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In field flux method speed control of DC Motor is constant hp drive below the base speed. constant torque drive above the base speed. constant torque drive below the base speed. constant power drive above base speed. constant hp drive below the base speed. constant torque drive above the base speed. constant torque drive below the base speed. constant power drive above base speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 2, 4, 5, 6 3, 4, 5 1, 2, 5 2, 3, 6 2, 4, 5, 6 3, 4, 5 1, 2, 5 2, 3, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Capacitor fitted with ceiling / table fans is of the value of 0.1 µF. 1 - 2 µF. 2 - 3 µF. 5 - 10 F. 0.1 µF. 1 - 2 µF. 2 - 3 µF. 5 - 10 F. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the effect of armature reaction ? Armature flux weakens the main field flux. Both option B and C. None of the options. Armature flux distorts the main field flux. Armature flux weakens the main field flux. Both option B and C. None of the options. Armature flux distorts the main field flux. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine, for the same value of Æ, Z and N; which one of the following statements is correct? Armature emf is less with wave winding than with lap winding. Armature emf is same as long as the flux density in the air gap remains the same. Armature emf is more with wave winding than with lap winding. Armature emf depends on weather the machine is running as a motor or generator. Armature emf is less with wave winding than with lap winding. Armature emf is same as long as the flux density in the air gap remains the same. Armature emf is more with wave winding than with lap winding. Armature emf depends on weather the machine is running as a motor or generator. ANSWER DOWNLOAD EXAMIANS APP