These are some multiple choice questions on dc generators please check out and comment if you have any doubts...
1) A P-pole lap wound dc machine had an armature current Ia. The conductor current in the armature winding is
A) Ia
B) Ia/P
C) PIa
D) none of the above
Ans:B
2) For a 4-pole machine wave winding is impossible with .............armature conductors.
A) 30
B) 32
C) 34
D) 38
Ans:B
3) The dummy coils in dc machine are useful to
A) increase the efficiency
B) improve the commutation
C) reduce the cost of the machine
D) maintain mechanical balance of armature
Ans:D
4) The number of parallel paths for a 4-pole duplex lap winding will be
A) 2
B) 4
C) 6
D) 8
Ans:D
5) welding generator will have
A) lap winding
B) wave winding
C) either lap or wave winding
D) none of these
Ans:A
6) Width of a carbon brush should be equal to
A) less than the width of one commutator segment.
B) the width of 1 or 2 commutator segment.
C) the width of 2 or 3 commutator segment.
D) the width of more than 3 commutator segments.
Ans:C
7) What are slot wedges in a dc machine made of?
A) Mild steel
B) Silicon steel
C) Fibre
D) Cast iron
Ans:C
8) Which of the following is not a part of dc machine?
A) Armature
B) Commutator
C) Field winding
D) Damping winding
Ans:D
9) The coil span
A) must be exactly equal to pole-pitch
B) can never be equal to pole-pitch
C) may or may not be exactly equal to pole-pitch
D) None of the above
Ans:C
10) For both lap and wave winding, there are as many commutator bars as the number of
A) armature conductors
B) winding elements
C) poles
D) slots
Ans:B
Thanks for reading my post. keep visiting my blog.......
1) A P-pole lap wound dc machine had an armature current Ia. The conductor current in the armature winding is
A) Ia
B) Ia/P
C) PIa
D) none of the above
Ans:B
2) For a 4-pole machine wave winding is impossible with .............armature conductors.
A) 30
B) 32
C) 34
D) 38
Ans:B
3) The dummy coils in dc machine are useful to
A) increase the efficiency
B) improve the commutation
C) reduce the cost of the machine
D) maintain mechanical balance of armature
Ans:D
4) The number of parallel paths for a 4-pole duplex lap winding will be
A) 2
B) 4
C) 6
D) 8
Ans:D
5) welding generator will have
A) lap winding
B) wave winding
C) either lap or wave winding
D) none of these
Ans:A
6) Width of a carbon brush should be equal to
A) less than the width of one commutator segment.
B) the width of 1 or 2 commutator segment.
C) the width of 2 or 3 commutator segment.
D) the width of more than 3 commutator segments.
Ans:C
7) What are slot wedges in a dc machine made of?
A) Mild steel
B) Silicon steel
C) Fibre
D) Cast iron
Ans:C
8) Which of the following is not a part of dc machine?
A) Armature
B) Commutator
C) Field winding
D) Damping winding
Ans:D
9) The coil span
A) must be exactly equal to pole-pitch
B) can never be equal to pole-pitch
C) may or may not be exactly equal to pole-pitch
D) None of the above
Ans:C
10) For both lap and wave winding, there are as many commutator bars as the number of
A) armature conductors
B) winding elements
C) poles
D) slots
Ans:B
Thanks for reading my post. keep visiting my blog.......
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