Electrical Machines What is the phase difference between two windings of A.C servomotor ? 120°. 30°. 90°. 60°. 120°. 30°. 90°. 60°. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature reaction depends on which of the following? magnitude of load current both 1 and 2 None of these power factor of load magnitude of load current both 1 and 2 None of these power factor of load ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For high current and low voltage rating which winding is employed to DC machine? Lap winding. Wave winding. No wave and lap winding. Both wave and lap winding. Lap winding. Wave winding. No wave and lap winding. Both wave and lap winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC Shunt Motor having armature resistance of 0.5 Ω and 2A armature current at no-load, when the armature current is changed to 20A at loaded condition the speed is 1000 r.p.m. What is the speed at no-load? 4575.4 r.p.m. 1037.5 r.p.m. 963.8 r.p.m. 1130 r.p.m. 4575.4 r.p.m. 1037.5 r.p.m. 963.8 r.p.m. 1130 r.p.m. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines φA DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the speed when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 940 RPM 960 RPM 920 RPM 970 RPM 940 RPM 960 RPM 920 RPM 970 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, if P be the number of poles and N be the rpm of the rotor, then frequency of magnetic reversals will be PN/60. PN/3000. PN/120. PN/2. PN/60. PN/3000. PN/120. PN/2. ANSWER DOWNLOAD EXAMIANS APP