| 1. | Natural oil cooling is used for transformers upto a rating of ? | |
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3000 kVA
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1000 kVA
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500 kVA
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250 kVA
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Report Question| 2. | ln a transformer routine efficiency depends upon ? | |
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supply frequency
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load current
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power factor of load
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both (b) and (c)
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| 3. | Which winding in a transformer has more number of turns ? | |
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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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| 4. | Which of the following is not a part of transformer installation ? | |
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Conservator
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Breather
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Buchholz relay
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Exciter
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| 5. | Buchholz relay is used on ? | |
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welding transformers
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air-cooled transformers
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furnace transformers
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oil cooled transformers
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| 6. | Buchholz relay is used in ? | |
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motor protection
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line protection
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transformer protection
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none of the above
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| 7. | When a delta connected primary of a 3-phase transformer is connected to 3- phase supply ? | |
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magnetizing current in phase winding will carry third harmonics but line current will be free from it
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magnetizing current in phase winding will contain third harmonics and line current will also contain third harmonics
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magnetizing current in phase winding will not contain third harmonics but line current will contain third harmonics
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none of the above
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| 8. | 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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| 9. | 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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| 10. | A Buchholz relay can be installed on ? | |
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auto-transformers
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air-cooled transformers
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welding transformers
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oil cooled transformers
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