Top 150+ Solved Single Phase Induction Motor MCQ Questions Answer
Q. In a single phase motor the centrifugal switch
a. disconnects auxiliary winding of the motor
b. disconnects main winding of the motor
c. reconnects the main winding the motor
d. reconnects the auxiliary winding of the motor
Q. The running winding of a single phase motor on testing with meggar is found to beground. Most probable location of the ground will be
a. at the end connections
b. at the end terminals
c. anywhere on the winding inside a slot
d. at the slot edge where coil enters or comes out of the slot
Q. A capacitor-start single phase induction motor is switched on to supply with itscapacitor replaced by an inductor of equivalent reactance value. It will
a. start and then stop
b. start and run slowly
c. start and run at rated speed
d. not start at all
Q. Which of the following motors is used in mixies ?
a. Repulsion motor
b. Reluctance motor
c. Hysteresis motor
d. Universal motor
Q. Which of the following motors is inherently self starting ?
a. Split motor
b. Shaded-pole motor
c. Reluctance motor
d. None of these
Q. The direction of rotation of an hysteresis motor is determined by
a. interchanging the supply leads
b. position of shaded pole with respect to main pole
c. retentivity of the rotor material
d. none of these
Q. Burning out of windings is due to
a. short circuited capacitor
b. capacitor value hiving changed
c. open circuiting of capacitor
d. none of the above
Q. Direction of rotation of a split phase motor can be reversed by reversing theconnection of
a. running winding only
b. starting winding only
c. either (a) or (b)
d. both (a) and (b)
Q. Short-circuiter is used in
a. repulsion induction motor
b. repulsion motor
c. repulsion start induction run motor
d. none of the above
Q. The range of efficiency for shaded pole motors is
a. 95% to 99%
b. 80% to 90%
c. 50% to 75%
d. 5% to 35%
Q. In a capacitor start single-phase motor, when capacitor is replaced by a resistance
a. torque will increase
b. the motor will consume less power
c. motor will run in reverse direction
d. motor will continue to run in same direction
Q. The power factor of a single-phase induction motor is usually
a. lagging
b. always leading
c. unity
d. unity to 0.8 leading
Q. A hysteresis motor works on the principle of
a. hysteresis loss
b. magnetisation of rotor
c. eddy current loss
d. electromagnetic induction
Q. Which of the following motor will give the highest starting torque ?
a. D.C. shunt motor
b. Schrage motor
c. Repulsion start and induction run motor
d. Universal motor