Electrical Machines What is the phase difference between two windings of A.C servomotor ? 120°. 30°. 60°. 90°. 120°. 30°. 60°. 90°. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Ward-Leonard system for controlling the speed of a DC motor is used where The speed in both the direction is required. Very fine speed control over the whole range from zero to normal speed is required. All of above. The accuracy in speed control is required. The speed in both the direction is required. Very fine speed control over the whole range from zero to normal speed is required. All of above. The accuracy in speed control is required. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Voltage across the open circuited field termninals of a synchorous machine under slip test is A modulated supply frequency AC voltage with slip frequency envelop. DC of slip frequency. AC of supply frequency. DC. A modulated supply frequency AC voltage with slip frequency envelop. DC of slip frequency. AC of supply frequency. DC. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In travelling cranes for swing action which motor is preferred? Reluctance motor. DC series motor. Capacitor type induction motors. AC slip ring IM. Reluctance motor. DC series motor. Capacitor type induction motors. AC slip ring IM. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Flashing the field of DC generator means creating residual magnetism by a DC source. making the magnetic losses forces parallel. neutralising residual magnetism. increasing flux density by adding extra turns of winding. creating residual magnetism by a DC source. making the magnetic losses forces parallel. neutralising residual magnetism. increasing flux density by adding extra turns of winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 200 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 Ω. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by 10%, the ratio of motor speed to generator speed is 0.87 1.06 0.95 0.96 0.87 1.06 0.95 0.96 ANSWER DOWNLOAD EXAMIANS APP