Synchronous Motors By which of the following methods the constant speed of a synchronous motor can be changed to new fixed value ? By changing the load By changing the supply frequency By interchanging any two phases By changing the applied voltage By changing the load By changing the supply frequency By interchanging any two phases By changing the applied voltage ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors Hunting in a synchronous motor cannot be due to windage friction variable load variable supply voltage variable frequency windage friction variable load variable supply voltage variable frequency ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The duration of sudden short-circuit test on a synchronous motor is usually about one minute one hour None of these one second one minute one hour None of these one second ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors In a 3-phase synchronous motor, the negative phase sequence exists when the motor is under-loaded over-loaded None of these supplied with unbalanced voltage under-loaded over-loaded None of these supplied with unbalanced voltage 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 rotor strengthens the rotating field causing more motor current The increased load has to take more current The back e.m.f. decreases causing an increase in motor current The rotor by shifting its phase backward causes motor to take more current The rotor strengthens the rotating field causing more motor current The increased load has to take more current The back e.m.f. decreases causing an increase in motor current ANSWER DOWNLOAD EXAMIANS APP
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