| 1. | ln a step-down transformer, there is a change of 15 A in the load current. This results in change of supply current of ? | |
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less than 15 A
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more than 15 A
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15 A
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none of the above
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Report Question| 2. | In a power or distribution transformer about 10 per cent end turns are heavily insulated ? | |
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to with stand the high voltage drop due to line surge produced by the shunting capacitance of the end turns
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to absorb the line surge voltage and save the winding of transformer from damage
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to reflect the line surge and save the winding of a transformer from damage
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none of the above
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| 3. | Which type of winding is used in 3-phase shell-type transformer ? | |
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Circular type
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Sandwich type
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Cylindrical type
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Rectangular type
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| 4. | Which of the following test on a transformer provides information about regulation, efficiency and heating under load conditions ? | |
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Back to back test
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Short circuit test
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Swinburne's test
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Open circuit test
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| 5. | ln the transformer following winding has got more cross-sectional area ? | |
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Low voltage winding
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High voltage winding
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Primary winding
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Secondary winding
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| 6. | The noise resulting from vibrations of laminations set by magnetic forces, is termed as ? | |
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magneto strication
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buo
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hum
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zoom
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| 7. | The function of conservator in a transformer is ? | |
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to project against internal fault
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to reduce copper as well as core losses
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to cool the transformer oil
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to take care of the expansion and contraction of transformer oil due to variation of temperature of surroundings
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| 8. | Silicon steel used in laminations mainly reduces ? | |
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hysteresis loss
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eddy current losses
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copper losses
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all of the above
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| 9. | Negative voltage regulation is indicative that the load is ? | |
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capacitive only
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inductive only
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inductive or resistive
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none of the above
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| 10. | The transformer laminations are insulated from each other by ? | |
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mica strip
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thin coat of varnish
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paper
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any of the above
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