A. It requires more maintenance of commutator and other mechanical devices
B. It makes quite a bit of noise on starting
C. In fractional horse power motors, it has replaced the capacitor motors
D. It is not easily reversed
Related Mcqs:
- The repulsion-start induction-run motor is used because of___________?
A. good power factor
B. high efficiency
C. minimum cost
D. high starting torque - Which of the following statements regarding reluctance-start motor is incorrect ?
A. It is similar to reluctance motor
B. It is basically an induction motor and not a synchronous one
C. So far as its basic working principle is concerned, it is similar to shaded pole motor
D. the air-gap between rotor and salient poles is non- uniform - Speed torque characteristic of a repulsion induction motor is similar to that of a D.C____________?
A. shunt motor
B. series motor
C. compound motor
D. separately excited motor - Which of the following statements regarding hysteresis motor is in incorrect?
A. It is extremely sensitive to fluctuations in supply voltage
B. Its high starting torque is due to its high rotor hysteresis loss
C. It is extremely quiet in operation
D. It accelerates from rest to full-speed almost instantaneously - Which of the following statements regarding two value capacitor motor is incorrect ?
A. It is a reversing motor
B. It is preferred to permanent-split single-value capacitor motor where frequent reversals are required
C. It has low starting as well as rushing currents
D. It has high starting torque - Which of the following statements regarding a reluctance motor is incorrect ?
A. It cannot be reversed, ordinarily
B. It requires no D.C. field excitation for its operation
C. It is nothing else but a single-phase, salient pole synchronous-induction motor
D. Its squirrel cage-rotor is of unsym-metrical magnetic construction in order to vary reluctance path between stator and rotor - Which of the following statements regarding single-phase induction motors correct?
A. It requires only one winding
B. It can rotate in one direction only
C. It is self-starting
D. It is not self-starting - A capacitor-start single phase induction motor is switched on to supply with its capacitor 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 - In repulsion motor, maximum torque is developed when____________?
A. brush axis is at 45° electrical to the field axis
B. brush axis coincides with the field axis
C. brush axis is at 90° electrical to the field axis
D. none of the above - A repulsion motor is equipped with__________?
A. slip rings
B. commutator
C. both A. and (b)
D. none of the above
