1. Which of the following are the applications of D.C. system ?
2. Which of the following methods may be used to convert A.C. system to D.C. ?
3. In a single phase rotary converter the number of slip rings will be
4. A synchronous converter can be started
5. A rotary converter is a single machine with
6. A rotary converter combines the function of
7. Which of the following is reversible in action ?
8. Which of the following metals is generally manufactured by electrolysis process ?
9. With a motor converter it is possible to obtain D.C. voltage only upto
10. Normally, which of the following is used, when a large-scale conversion from AC. to D.C. power is required ?
11. A rotary converter in general construction and design, is more or less like
12. A rotary converter operates at a
13. In which of the following applications, direct current is absolutely essential ?
14. Which of the following AC. motors is usually used in large motor-generator sets?
15. In a rotary converter armature currents are
16. In which of the following equipment direct current is needed ?
17. In a rotary converter I2R losses as compared to a D.C. generator of the same size will be
18. In a mercury arc rectifier positive ions are attracted towards
19. Mercury, in arc rectifiers, is chosen for cathode because
20. The ionization potential of mercury is approximately
21. The potential drop in the arc, in a mercury arc rectifier, varies
22. The voltage drop between the anode and cathode, of a mercury arc rectifier comprises of the following
23. Glass rectifiers are usually made into units capable of D.C. output (maximum continuous rating) of
24. The voltage drop at anode, in a mercury arc rectifier is due to
25. The internal efficiency of a mercury arc rectifier depends on
26. If cathode and anode connections in a mercury arc rectifier are inter changed
27. The cathode voltage drop, in a mercury arc rectifier, is due to
28. To produce cathode spot in a mercury arc rectifier
29. The advantage of mercury arc rectifier is that
30. In a mercury pool rectifier, the voltage drop across its electrodes
31. In a three-phase mercury arc rectifiers each anode conducts for
32. In a mercury arc rectifier characteristic blue luminosity is due to
33. Which of the following mercury arc rectifier will deliver least undulating current?
34. In a glass bulb mercury arc rectifier the maximum current rating is restricted to
35. In a mercury arc rectifier______ flow from anode to cathode
36. When a rectifier is loaded which of the following voltage drops take place ?
37. On which of the following factors the number of phases for which a rectifier should be designed depend ?
38. A mercury arc rectifier possesses ________ regulation characteristics
39. It is the_______of the transformer on which the magnitude of angle of overlap depends.
41. In a grid control of mercury arc rectifiers when the grid is made positive relative to cathode, then it ______ the electrons on their may to anode.
42. In mercury arc rectifiers having grid, the arc can be struck between anode and cathode only when the grid attains a certain potential, this potential being known as
43. In phase-shift control method the control is carried out by varying the of grid voltage.
44. In a phase-shift control method, the phase shift between anode and grid voltages can be achieved by means of
45. The metal rectifiers are preferred to valve rectifiers due to which of the following advantages ?
46. Which of the following statement is incorrect ?
47. The efficiency of the copper oxide rectifier seldom exceeds
48. Copper oxide rectifier is usually designed not to operate above
49. Selenium rectifier can be operated at temperatures as high as
50. In selenium rectifiers efficiencies ranging from ______ to ______ percent are attainable
51. Ageing of a selenium rectifier may change the output voltage by
52. The applications of selenium rectifiers are usually limited to potential of
53. Which of the following rectifiers have been used extensively in supplying direct current for electroplating ?
54. A commutating rectifier consists of commutator driven by
55. Which of the following rectifiers are primarily used for charging of low voltage batteries from AC. supply ?
56. The efficiency of an electrolytic rectifier is nearly
57. Which of the following is the loss within the mercury arc rectifier chamber ?
58. The metal rectifiers, as compared to mercury arc rectifiers
59. In a mercury arc rectifier, the anode is usually made of
60. The ignited or auxiliary anode in mercury arc rectifier is made of
2. Which of the following methods may be used to convert A.C. system to D.C. ?
3. In a single phase rotary converter the number of slip rings will be
4. A synchronous converter can be started
5. A rotary converter is a single machine with
6. A rotary converter combines the function of
7. Which of the following is reversible in action ?
8. Which of the following metals is generally manufactured by electrolysis process ?
9. With a motor converter it is possible to obtain D.C. voltage only upto
10. Normally, which of the following is used, when a large-scale conversion from AC. to D.C. power is required ?
11. A rotary converter in general construction and design, is more or less like
12. A rotary converter operates at a
13. In which of the following applications, direct current is absolutely essential ?
14. Which of the following AC. motors is usually used in large motor-generator sets?
15. In a rotary converter armature currents are
16. In which of the following equipment direct current is needed ?
17. In a rotary converter I2R losses as compared to a D.C. generator of the same size will be
18. In a mercury arc rectifier positive ions are attracted towards
19. Mercury, in arc rectifiers, is chosen for cathode because
20. The ionization potential of mercury is approximately
21. The potential drop in the arc, in a mercury arc rectifier, varies
22. The voltage drop between the anode and cathode, of a mercury arc rectifier comprises of the following
23. Glass rectifiers are usually made into units capable of D.C. output (maximum continuous rating) of
24. The voltage drop at anode, in a mercury arc rectifier is due to
25. The internal efficiency of a mercury arc rectifier depends on
26. If cathode and anode connections in a mercury arc rectifier are inter changed
27. The cathode voltage drop, in a mercury arc rectifier, is due to
28. To produce cathode spot in a mercury arc rectifier
29. The advantage of mercury arc rectifier is that
30. In a mercury pool rectifier, the voltage drop across its electrodes
31. In a three-phase mercury arc rectifiers each anode conducts for
32. In a mercury arc rectifier characteristic blue luminosity is due to
33. Which of the following mercury arc rectifier will deliver least undulating current?
34. In a glass bulb mercury arc rectifier the maximum current rating is restricted to
35. In a mercury arc rectifier______ flow from anode to cathode
36. When a rectifier is loaded which of the following voltage drops take place ?
37. On which of the following factors the number of phases for which a rectifier should be designed depend ?
38. A mercury arc rectifier possesses ________ regulation characteristics
39. It is the_______of the transformer on which the magnitude of angle of overlap depends.
41. In a grid control of mercury arc rectifiers when the grid is made positive relative to cathode, then it ______ the electrons on their may to anode.
42. In mercury arc rectifiers having grid, the arc can be struck between anode and cathode only when the grid attains a certain potential, this potential being known as
43. In phase-shift control method the control is carried out by varying the of grid voltage.
44. In a phase-shift control method, the phase shift between anode and grid voltages can be achieved by means of
45. The metal rectifiers are preferred to valve rectifiers due to which of the following advantages ?
46. Which of the following statement is incorrect ?
47. The efficiency of the copper oxide rectifier seldom exceeds
48. Copper oxide rectifier is usually designed not to operate above
49. Selenium rectifier can be operated at temperatures as high as
50. In selenium rectifiers efficiencies ranging from ______ to ______ percent are attainable
51. Ageing of a selenium rectifier may change the output voltage by
52. The applications of selenium rectifiers are usually limited to potential of
53. Which of the following rectifiers have been used extensively in supplying direct current for electroplating ?
54. A commutating rectifier consists of commutator driven by
55. Which of the following rectifiers are primarily used for charging of low voltage batteries from AC. supply ?
56. The efficiency of an electrolytic rectifier is nearly
57. Which of the following is the loss within the mercury arc rectifier chamber ?
58. The metal rectifiers, as compared to mercury arc rectifiers
59. In a mercury arc rectifier, the anode is usually made of
60. The ignited or auxiliary anode in mercury arc rectifier is made of
No comments:
Post a Comment