Star/star transformers work satisfactorily when?

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asked Mar 19, 2018 by anonymous

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Delta/star transformer works satisfactorily when?

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asked Apr 29, 2018 by anonymous

If an unsymmetrical line to ground fault occurs at the secondary terminals of a delta/star, ungrounded

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In the transformer which winding has got more cross-sectional area?

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The no load current in a transformer lags behind the applied voltage by an angle of about?

Last answer: The no load current in a transformer lags behind the applied voltage by an angle of about 75°.

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The maximum efficiency of a distribution transformer is?

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No-load current of a transformer has?

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Spacers are provided between adjacent coils?

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Greater the secondary leakage flux?

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asked Mar 19, 2018 by anonymous

The purpose of providing iron core in a step-up transformer is?

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asked Mar 19, 2018 by anonymous

The power transformer is a constant?

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asked Mar 19, 2018 by anonymous

In a transformer the tappings are generally provided on?

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The use of higher flux density in the transformer design?

Last answer: The use of higher flux density in the transformer design reduces weight per kVA.

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asked Mar 19, 2018 by anonymous

The chemical used in breather for transformer should have the quality of?

Last answer: The chemical used in breather for transformer should have the quality of cleansing the transformer oil.

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asked Mar 19, 2018 by anonymous

The chemical used in breather is?

Last answer: The chemical used in breather is silica gel.

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An ideal transformer has infinite values of primary and secondary inductances. The statement is?

Last answer: An ideal transformer has infinite values of primary and secondary inductances. The statement is false.

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asked Mar 19, 2018 by anonymous

The transformer ratings are usually expressed in terms of?

Last answer: The transformer ratings are usually expressed in terms of kVA.

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asked Mar 19, 2018 by anonymous

Material used for construction of transformer core is usually?

Last answer: Material used for construction of transformer core is usually silicon steel.

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asked Mar 19, 2018 by anonymous

The thickness of laminations used in a transformer is usually?

Last answer: The thickness of laminations used in a transformer is usually 0.4 mm to 0.5 mm.

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asked Mar 19, 2018 by anonymous

The function of conservator in a transformer is?

Last answer: conservator or a reservoir tank for insulating oil in transformer which used for balanced the onload oil level with help of oil level indicator which mount on middle part of reservoir tank.

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asked Mar 19, 2018 by anonymous

A transformer oil must be free from?

Last answer: A transformer oil must be free from moisture.

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asked Mar 19, 2018 by anonymous

Gas is usually not liberated due to dissociation of transformer oil unless the oil temperature exceeds?

Last answer: Gas is usually not liberated due to dissociation of transformer oil unless the oil temperature exceeds 150°C.

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asked Mar 19, 2018 by anonymous

The main reason for generation of harmonics in a transformer could be?

Last answer: The main reason for generation of harmonics in a transformer could be saturation of core.

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asked Mar 19, 2018 by anonymous

The magnetising current of a transformer is usually small because it has?

Last answer: The magnetising current of a transformer is usually small because it has small air gap.

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asked Mar 19, 2018 by anonymous

The leakage flux in a transformer depends upon?

Last answer: The leakage flux in a transformer depends upon load current.

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anonymous · Answer 1 · 2018-03-19T21:18:35+0000

answered Mar 19, 2018 by anonymous

Star/star transformers work satisfactorily when load is balanced .

Star/star transformers work satisfactorily when?

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