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 lagging power factor with over-excitation no change of power factor leading power factor with over-excitation leading power factor with under-excitation lagging power factor with over-excitation no change of power factor leading power factor with over-excitation ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The minimum armature current of the synchronous motor corresponds to operation at zero power factor leading 0.707 power factor lagging 0.707 power factor leading unity power factor zero power factor leading 0.707 power factor lagging 0.707 power factor leading unity power factor ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The pull out torque of a synchronous motor is generally ______ times its full-load torque. 6 to 9 1.25 to 3.5 5 to 10 0.5 6 to 9 1.25 to 3.5 5 to 10 0.5 ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as pull-in torque pull-out torque None of these pull-up torque pull-in torque pull-out torque None of these pull-up torque ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors The percentage slip in case of a synchronous motor is 0.005 1 0.01 zero 0.005 1 0.01 zero ANSWER DOWNLOAD EXAMIANS APP
Synchronous Motors When a synchronous motor is on no load, the torque angle is about ________ 30° electrical 0° electrical 90° electrical 45° electrical 30° electrical 0° electrical 90° electrical 45° electrical ANSWER DOWNLOAD EXAMIANS APP