| 1. | When a 440/220 V transformer is connected to 400 V D.C. supply ? | |
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the transformer may burn
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the output will be zero volt
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the output will be 220 V
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the output will be less than 230 V
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Report Question| 2. | Which of the following is not a fitting on a transformer ? | |
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Commutator
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Breather
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Conservator
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Buchholz's relay
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| 3. | Burden of a current transformer is usually expressed in ? | |
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amperes
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volts
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volt amperes
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kilowatt
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| 4. | The transformation ratio of a transformer, for a given application ? | |
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depends on secondary load
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is constant but not fixed
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is fixed but not constant
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none of the above
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| 5. | While performing a short-circuit test on a transformer, usually low-voltage side is short-circuited because it has ? | |
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low insulation
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easy access
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lower terminal voltage and higher current rating
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more number of turns
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| 6. | Increase in secondary current of a transformer brings about increase in primary current. This is possible because ? | |
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primary and secondary windings are capacitively coupled
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primary and secondary windings are inductively coupled
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primary and secondary windings are conductively coupled
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none of the above
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| 7. | In order to find the full-load efficiency of a transformer the losses which must be known ? | |
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may be found by performing open circuit and short-circuit tests
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may be found by measuring winding resistances and calculating the I2R losses
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may be found by measuring the input to the primary with secondary open
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cannot be found except by actually loading the transformer fully
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| 8. | While rising and while falling, if a wave is symmetrical, it contains ? | |
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even harmonics in addition to fundamental
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odd harmonics in addition to fundamental
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both odd and even harmonics in addition to fundamental
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none of the above
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| 9. | Dust should never be allowed to accumulate on the windings and core of a dry. type transformer because it ? | |
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reduces dissipation of heat
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may short-circuit the windings
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absorbs oil and grease
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tends to corrode the metal surface
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| 10. | For parallel operation of two single phase transformers the essential condition is that they should have the same ? | |
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voltage ratio
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percentage impedance
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polarity
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phase sequence
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