Quiz No:60 Industrial Drives RRB , Coal India , PSC , PWD , Engineering diploma Level

1. In ……… the speed can be varied by changing the position of brushes.

 
 
 
 

2. In which of the following applications variables speed operation is preferred?

 
 
 
 

3. Heavy duty cranes are used in—

 
 
 
 

4. The travelling speed of cranes varies from—

 
 
 
 

5. The capacity of a crane is expressed in terms of-

 
 
 
 

6. Which of the following happens when star-delta starter is used?

 
 
 
 

7. For which of the following applications motor has to start with high acceleration?

 
 
 
 

8. Which of the following types of motor enclosure is safest?

 
 
 
 

9. A synchronous motor is found to be more economical when the load is above—

 
 
 
 

10. The advantage of a synchronous motor in addition to its constant speed is—

 
 
 
 

11. The characteristics of drive for crane hoisting and lowering is—

 
 
 
 

12. The capacity of a crane is expressed in terms of-

 
 
 
 

13. The travelling speed of cranes varies from—

 
 
 
 

14. 15 minute rated motors are suitable for—

 
 
 
 

15. Light duty cranes are generally used in—

 
 
 
 

16. Heavy duty cranes are used in—

 
 
 
 

17. For handling fragile articles in a crane—

 
 
 
 

18. The range of horse power of electric motor drives for rolling mills is of the order of—

 
 
 
 

19. Motors preferred for rolling mills drive is—

 
 
 
 

20. The size of a excavator is usually expressed in terms of—

 
 
 
 

21. Which electromagnet is preferred for noiseless operation?

 
 
 
 

22. For high frequency choppers the device that is preferred is—

 
 
 
 

23. The number of operations per hour in case of class IV contactor will be around—

 
 
 
 

24. In case of saturable core reactors, the power gain varies from—

 
 
 
 

25. A magnetic amplifier can be used for the control of—