A. d.c. series machines
B. d.c. shunt machines
C. d.c. compound machines
D. any of the above
Related Mcqs:
- A synchronous motor installed at the receiving end substation operates with such an excitation that it takes power at lagging power factor. Now if the applied voltage of the synchronous motor goes down, the power factor of the synchronous motor will___________?
A. remain same
B. go down
C. improve
D. none of the above - When the rotor speed, in a synchronous machine, becomes more than the synchronous speed during hunting, the damper bars develop_________________?
A. inductor motor torque
B. induction generator torque
C. synchronous motor torque
D. d.c. motor toque
E. none of the above - A synchronous motor can be used as a synchronous capacitor when it is____________?
A. under-loaded
B. over-loaded
C. under-excited
D. over-excited - A synchronous motor can develop synchronous torque:
A. when under loaded
B. while over-excited
C. only at synchronous speed
D. below or above synchronous speed - A three-phase synchronous motor will have_____________?
A. no slip-rings
B. one slip-ring
C. two slip-rings
D. three slip-rings - Which of the following resistances can be measured by conducting insulation resistance test on a synchronous motor ?
A. Phase to phase winding resistance
B. Stator winding to earthed frame
C. Rotor winding to earthed shaft
D. All of the above - If one-phase of a 3-phase synchronous motor is short-circuited, motor will ______________?
A. will refuse to start
B. will overheat in spots
C. will not come upto speed
D. will fail to pull into step - Mostly, synchronous motors are of_____________?
A. alternator type machines
B. induction type machines
C. salient pole type machines
D. smooth cylindrical type machines - A synchronous motor can operate at____________?
A. lagging power factor only
B. leading power factor only
C. unity power factor only
D. lagging, leading and unity power factors - If the field winding of an unloaded salient pole synchronous motor is open circuited, the motor will__________?
A. stop
B. run as induction motor
C. function as static condenser
D. burn with dense smoke
