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 1, 2, 3 2, 3, 4, 5 2, 3, 4 2, 3 ,5 1, 2, 3 2, 3, 4, 5 2, 3, 4 2, 3 ,5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the actual arrangement of series wound generator? Armature and field both are parallel. Armature and field both are in series with the load. Armature and field both are connected. Armature winding is in series with load. Armature and field both are parallel. Armature and field both are in series with the load. Armature and field both are connected. Armature winding is in series with load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When excitation is increased (over excitation), the synchronous generator operates at leading power factor. any of the above. unity power factor. lagging power factor. leading power factor. any of the above. unity power factor. lagging power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Rotating magnetic field is produced in an induction motor because of either stator winding or rotor winding. None of these rotor winding. stator winding. either stator winding or rotor winding. None of these rotor winding. stator winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 4 pole IM is supplied from a 50 Hz source. Calculate rotor frequency when rotor runs 600 rpm? 30 Hz. 35 Hz. Can be determined. 20 Hz. 30 Hz. 35 Hz. Can be determined. 20 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 500 V, 120 KW, 50 Hz, star connected synchronous motor operating at 0.8 power factor leading has full load efficiency of 91%. The armature resistance is equal to 0.08Ω. The magnitude of armature current is nearly equal to 127 A. 190 A. 173 A. 240 A. 127 A. 190 A. 173 A. 240 A. ANSWER DOWNLOAD EXAMIANS APP