The main disadvantage of the Ward-Leonard control method is______________?

Related Mcqs:

1. Speed control by Ward Leonard method gives uniform speed variation_____________?

   A. in one direction B. in both directions C. below normal speed only D. above normal speed only...

2. Ward Leonard method of speed control is basically a______________?

   A. field control method B. armature controlled method C. field diverter D. frequency control method...

3. Ward-Leonard control is basically a____________?

   A. voltage control method B. field divertor method C. field control method D. armature resistance control method...

4. In Ward-Leonard control the lower limit of speed is imposed by________?

   A. residual magnetism of the generator B. core losses of motor C. mechanical losses of motor and generator together D. all of the above...

5. In a D.C. shunt motor, speed is______________?

   A. independent of armature current B. directly proportional to the armature current C. proportional to the square of the current D. inversely proportional to the armature current...

6. The mechanical power developed by a shunt motor will be maximum when the ratio of back e.m.f. to applied voltage is______________?

   A. 4.0 B. 2.0 C. 1.0 D. 0.5...

7. The condition for maximum power in case of D.C. motor is______________?

   A. back e.m.f. = 2 x supply voltage B. back e.m.f. = | x supply voltage C. supply voltage = | x back e.m.f D. supply voltage = back e.m.f...

8. The speed of a motor falls from 1100 r.p.m. at no-load to 1050 r.p.m. at rated load. The speed regulation of the motor is______________?

   A. 2.36% B. 4.76% C. 6.77% D. 8.84%...

9. The condition for maximum efficiency for a D.C. generator is______________?

   A. eddy current losses = stray losses B. hysteresis losses = eddy current losses C. copper losses = 0 D. variable losses = constant losses...

10. Which of the following method of speed control of D.C. machine will offer minimum efficiency ?

    A. Voltage control method B. Field control method C. Armature control method D. All above methods...