| 1. | Natural air cooling is generally restricted for transformers up to ? | |
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1.5 MVA
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5 MVA
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15 MVA
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50 MVA
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Report Question| 2. | If a transformer is continuously operated the maximum temperature rise will occur in ? | |
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core
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windings
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tank
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any of the above
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| 3. | If a transformer is switched on to a voltage more than the rated voltage ? | |
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its power factor will deteriorate
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its power factor will increase
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its power factor will remain unaffected
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its power factor will be zero
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| 4. | As per the name plate of a transformer the secondary normal voltage is 220 V. Which of the following statements about it is correct ? | |
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220 V is the no-load voltage
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The no-load voltage is more than 220V
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The secondary voltage increases with increasing load
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At a load which draws the rated current the voltage becomes less than 220 V
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| 5. | Oil impregnated paper condenser bushing is generally used on transformers operating at ? | |
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132 kV
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66 kV
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33 kV
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11 kV
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| 6. | Buchholz's relay gives warning and protection against ? | |
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electrical fault inside the transformer itself
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electrical fault outside the transformer in outgoing feeder
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either of the above
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none of the above
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| 7. | Which of the following parts of a transformer is likely to suffer maximum damage due to excessive temperature rise ? | |
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Winding insulation
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Copper winding
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Core laminations
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Dielectric strength of oil
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| 8. | A tap changer is used on a transformer for ? | |
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adjustments in secondary voltage
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adjustments in primary voltage
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adjustments in both primary and secondary voltages
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none of the above
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| 9. | The rating of a transformer is given in kVA instead of kW because ? | |
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kVA is fixed whereas kW depends on load p.f
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load power factor is often not known
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it has become customary
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total transformer loss depends on VA
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| 10. | For. given effective applied voltage of constant frequency eddy current losses ? | |
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become less with peaked wave shape of applied voltage
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independent of the wave shape of the applied voltage
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either of the above
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none of the above
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