| 1. | Two generators are running in parallel. One of the generators may run as motor for which of the following reasons ? | |
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The direction of that generator is reversed
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The speed of that generator is increased
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The field of that generator is weakened
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That generator takes large share of loads
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Report Question| 2. | Interpole flux should be sufficient to ? | |
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neutralise the commutating self-induced e.m.f.
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neutralise the armature reaction flux
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neutralise both the armature reaction flux as well as commutating e.m.f. induced in the coil
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perform none of the above functions
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| 3. | For generating large currents on D.C. generators which winding is generally preferred ? | |
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Progressive wave winding
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Lap winding
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Retrogressive wave winding
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Current depends on design
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| 4. | In D.C. generators, current to the external circuit from armature is given through ? | |
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commutator
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solid connection
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slip rings
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none of above
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| 5. | Two generators A and B have 6-poles each. Generator A has wave wound armature while generator B has lap wound armature. The ratio of the induced e.m.f. is generator A and B will be ? | |
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2 : 3
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3 : 1
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3 : 2
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1 : 3
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| 6. | A shunt generator running at 1000 r.p.m. has generated e.m.f as 200 V. If the speed increases to 1200 r.p.m., the generated e.m.f. will be nearly ? | |
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150 V
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176 V
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240 V
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290 V
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| 7. | When two D.C. series generators are running in parallel, an equilizer bar is used ? | |
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to increase the speed and hence generated e.m.f.
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to increase the series flux
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so that two similar machines will pass approximately equal currents to the load
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to reduce the combined effect of armature reaction of both machines
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| 8. | The number of armature parallel paths in a two-pole D.C. generator having duplex lap winding is ? | |
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2
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4
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6
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8
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| 9. | For both lap and wave windings, there are as many commutator bars as the number of ? | |
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slots
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armature conductors
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winding elements
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poles
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| 10. | A properly designed D.C. generator can have an overall efficiency of ? | |
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60%
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80%
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95%
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100%
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