Centrifugal switch disconnects the auxiliary winding of the motor at about ______ percent of synchronous speed?
A. 30 to 40
B. 70 to 80
C. 80 to 90
D. 100
Single Phase Induction Motors
Which of the following motors is used in a situation where load increases with speed ?
Which of the following motors is used in a situation where load increases with speed ?
A. Induction motor
B. Three-phase series motor
C. Schrage motor
D. Hysteresis motor
Which of the following motors is used for unity power factor ?
Which of the following motors is used for unity power factor ?
A. Hysteresis motor
B. Schrage motor
C. Universal motor
D. Reluctance motor
In repulsion motor, zero torque is developed when___________?
In repulsion motor, zero torque is developed when___________?
A. brush axis is 45° electrical to field axis
B. brush axis coincides with the field axis
C. brush axis is 90° electrical to field axis
D. both B. and (c)
The motor used for the compressors is____________?
The motor used for the compressors is____________?
A. d.c. series motor
B. shaded pole motor
C. capacitor-start capacitor-run motor
D. reluctance motor
The purpose of stator winding in the compensated repulsion motor is to_____________?
The purpose of stator winding in the compensated repulsion motor is to_____________?
A. provide mechanical balance
B. improve power factor and provide better speed regulation
C. prevent hunting in the motor
D. eliminate armature reaction
The rotor slots, in an induction motor, are usually not quite parallel to the shaft because it_____________?
The rotor slots, in an induction motor, are usually not quite parallel to the shaft because it_____________?
A. improves the efficiency
B. helps the rotor teeth to remain under the stator teeth
C. helps in reducing the tendency of the rotor teeth to remain under the stator teeth
D. improves the power factor
In a ceilingfan employing capacitor run motor____________?
In a ceilingfan employing capacitor run motor____________?
A. secondary winding surrounds the primary winding
B. primary winding surrounds the secondary winding
C. both are usual arrangements
D. none of the above
The speed/load characteristics of a universal motor is same as that of_____________?
The speed/load characteristics of a universal motor is same as that of_____________?
A. A.C. motor
B. D.C. shunt motor
C. D.C. series motor
D. none of the above
The shaded pole motor is used for__________?
The shaded pole motor is used for__________?
A. high starting torque
B. low starting torque
C. medium starting torque
D. very high starting torque