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 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 leading power factor with under-excitation leading power factor with over-excitation lagging power factor with over-excitation ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The induced e.m.f. in a synchronous motor working on leading power factor will be more than the supply voltage equal to the supply voltage less than the supply voltage None of these more than the supply voltage equal to the supply voltage less than the supply voltage None of these ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The pull out torque of a synchronous motor will ______ as the field excitation is increased. None of the listed here Remain unchanged Decrease Increase None of the listed here Remain unchanged Decrease Increase ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors A synchronous motor develops maximum power when load angle is 45° 120° 90° 60° 45° 120° 90° 60° ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The efficiency of a properly designed synchronous motor will usually fall in range 60 to 70% 99 to 99.5% 75 to 80% 85 to 95% 60 to 70% 99 to 99.5% 75 to 80% 85 to 95% ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The size of a synchronous motor decreases with the increase in Flux density All of the listed here Speed Horse power rating Flux density All of the listed here Speed Horse power rating ANSWER DOWNLOAD EXAMIANS APP