What will happen if transformer in parallel connection have different voltage ratio?

What will happen if transformer in parallel connection have different voltage ratio?
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1 Answer

Answer :

Two transformers in Parallel should have the same primary and secondary voltage ratings.  Any error in the voltage ratio would cause heavy circulating currents to flow between the transformers. This circulating current will result in a corresponding imbalance in the primary currents, and result in overloading of one transformer.  This circulating current will result in increased copper losses.
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Last Answer : A. there are 20 turns on primary one turn on secondary

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What is transformation ratio for step up, step down and isolation transformer?

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Description : What is voltage transformation ratio or turn ratio?

Last Answer : It is expressed as ratio of the primary and secondary voltages of transformer. or It is expressed as ratio of the primary and secondary turns of transformer. E1/ E2= T1/T2 = K

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What advantage has the star connection over the delta connection ?

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Last Answer : C) the voltage applied on primary side is low

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State and justify which of the following two transformers is better: Transformer A = 4% voltage regulation Transformer B = 6% voltage regulation

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Step-down transformer converts high voltage and low current into:

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A single phase transformer has resistance and reactance of 0.2 pu and 0.6 pu respectively. Its pu voltage

Description : A single phase transformer has resistance and reactance of 0.2 pu and 0.6 pu respectively. Its pu voltage regulation at 0.8 pf lagging would he

Last Answer : A single phase transformer has resistance and reactance of 0.2 pu and 0.6 pu respectively. Its pu voltage regulation at 0.8 pf lagging would he 0.52

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Last Answer : At 0.866 time voltage value

What is a capacitor voltage transformer?

Description : What is a capacitor voltage transformer? A) It is a transformer used in power systems to step up low voltage signals and provide extra high voltage B) It is a transformer used in power systems ... in power systems to step down extra high voltage signals and provide low voltage D) None of these

Last Answer : What is a capacitor voltage transformer? A) It is a transformer used in power systems to step up low voltage signals and provide extra high voltage B) It is a transformer used in power systems ... power systems to step down extra high voltage signals and provide low voltage D) None of these

A transformer at 25 Hz develops 20 W hysteresis loss and 50 W eddy current loss. If the applied voltage and

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A transformer cannot raise or lower the voltage of a D.C. supply because?

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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°.

When a given transformer is run at its rated voltage but reduced frequency, its?

Last Answer : When a given transformer is run at its rated voltage but reduced frequency, its core flux density is increased.

In a given transformer for a given applied voltage, losses which remain constant irrespective of load changes are?

Description : In a given transformer for a given applied voltage, losses which remain constant irrespective of load changes are?

Last Answer : In a given transformer for a given applied voltage, losses which remain constant irrespective of load changes are hysteresis and eddy current losses.

A good voltage regulation of a transformer means?

Description : A good voltage regulation of a transformer means?

Last Answer : A good voltage regulation of a transformer means output voltage fluctuation from no load to full load is least.

If a transformer is switched on to a voltage more than the rated voltage?

Description : If a transformer is switched on to a voltage more than the rated voltage?

Last Answer : If a transformer is switched on to a voltage more than the rated voltage its power factor will deteriorate.

does the high voltage side of Transformer winding have more number of turns?

Last Answer : yes High Voltage side of Transformer winding have more number of turns. and low voltage side of Transformer winding have less number of turns.