Following energized winding of a D.C. machine should not be opened as it would produce high inductive voltage which may be dangerous to personnel and may cause its own insulation failure.

Related Mcqs:

1. In case of D.C. machine winding, number of commutator segments is equal to______________?

   A. number of armature coils
   B. number of armature coil sides
   C. number of armature conductors
   D. number of armature turns

2. In a D.C. generator in case the resistance of the field winding is increased, then output voltage will____________?

   A. increase
   B. decrease
   C. remain unaffected
   D. fluctuate heavily

3. Which of the following generating machine will offer constant voltage on all loads?

   A. Self-excited generator
   B. Separately excited generator
   C. Level compounded generator
   D. All of the above

4. A sinusoidal voltage of 5 Hz is applied to the field of a shunt generator. The armature voltage wave will_____________?

   A. will be zero
   B. will be of 5 Hz
   C. will be of 5 xiVHz
   D. will be of v Hz 5

5. The terminal voltage of a series generator is 150 V when the load current is 5 A. If the load current is increased to 10 A, the terminal voltage will be____________?

   A. 150 V
   B. less than 150 V
   C. greater than 150 V
   D. none of the above

6. The following constitute short-circuit in the armature winding.

   A. Insulation failure between two commutator bars
   B. Insulation failure between two turns of a coil
   C. Two of more turns of the same coil getting grounded
   D. All of the above

7. For a D.C. generator when the number of poles and the number of armature conductors is fixed, then which winding will give the higher e.m.f___________ ?

   A. Lap winding
   B. Wave winding
   C. Either of A. and B. above
   D. Depends on other features of design

8. In case of a 4-pole D.C. generator provided with a two layer lap winding with sixteen coils, the pole pitch will be__________________?

   A. 4
   B. 8
   C. 16
   D. 32

9. In the case of lap winding resultant pitch is____________?

   A. multiplication of front and back pitches
   B. division of front pitch by back pitch
   C. sum of front and back pitches
   D. difference of front and back pitches

10. Wave winding is composed of_______________?

    A. any even number of conductors
    B. any odd number of conductors
    C. that even number which is exact multiple of poles + 2
    D. that even number which is exact multiple of poles