Synchronous Motors When load on a synchronous motor is increased, its armature current is increased provided, it is ______ All of these Over-excited Normally excited Under-excited All of these Over-excited Normally excited Under-excited ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors When load on an over-excited or under excited synchronous motor is increased, rate of change of its armature current as compared with that of power factor is twice more less equal twice more less equal ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The duration of sudden short circuit test on synchronous motor is usually about None of the listed here One second One hour One minute None of the listed here One second One hour One minute ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors A synchronous motor connected to infinite bus-bars has at constant full load, 100% excitation and unity power factor. On changing the excitation only, the armature current will have leading power factor with under-excitation leading power factor with over-excitation lagging power factor with over-excitation no change of power factor leading power factor with under-excitation leading power factor with over-excitation lagging power factor with over-excitation no change of power factor ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors In a synchronous motor, the rotor copper loss are met by ______ Motor input Supply lines Armature input Dc source Motor input Supply lines Armature input Dc source ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors As the load is applied to a synchronous motor, the motor takes more armature current because The rotor by shifting its phase backward causes motor to take more current The back e.m.f. decreases causing an increase in motor current The rotor strengthens the rotating field causing more motor current The increased load has to take more current The rotor by shifting its phase backward causes motor to take more current The back e.m.f. decreases causing an increase in motor current The rotor strengthens the rotating field causing more motor current The increased load has to take more current ANSWER DOWNLOAD EXAMIANS APP