| 1. | Number of tappings for each equilizer ring is equal to ? | |
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number of pole pairs
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number of poles
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number of parallel paths
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number of commutator segments
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Report Question| 2. | In D.C. generators, lap winding is used for ? | |
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high voltage, high current
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low voltage, high current
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high voltage, low current
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low voltage, low current
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| 3. | Which of the following generators will be preferred if they are required to be run in parallel ? | |
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Shunt generators
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Shunt generators
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Compound generators
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None of the above
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| 4. | Which one of the following generators is used for charging the batteries ? | |
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Shunt
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Series
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Compound
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Any of the above
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| 5. | In a separately excited generator supplying rated load the armature reaction ? | |
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is always present
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is always absent
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may be sometimes present
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none of the above
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| 6. | The series field of a short-shunt DC generator is excited by ? | |
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external current
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armature current
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shunt current
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load current
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| 7. | Satisfactory commutation of DC machines requires ? | |
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brushes should be of proper grade and size
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brushes should smoothly run in the holders
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smooth, concentric commutator properly undercut
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all of the above
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| 8. | In a D.C. generator ? | |
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external resistance = internal characteristic - armature reaction
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internal characteristic = magnetisation characteristic - ohmic drop
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external characteristic = magnetisation characteristic - ohmic drop - armature reaction
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magnetisation characteristic = external characteristic
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| 9. | The purpose of providing dummy coils in a generator is ? | |
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to reduce eddy current losses
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to enhance flux density
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to amplify voltage
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to provide mechanical balance for the rotor
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| 10. | Shunt generators are most suited for stable parallel operation because of their ? | |
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rising voltage characteristics
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identical voltage characteristics
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drooping voltage characteristics
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linear voltage characteristics
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