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The windings of a transformer have both resistance and inductance. When you apply an AC voltage to the primary winding, the opposition to current flow is a combination of resistance and inductive reactance; although the resistance of the winding is relatively low, its inductive reactance is high. The resulting impedance (the vector sum of resistance and inductive reactance) will, therefore, be high and the resulting current will be low.

If, on the other hand, you applied a DC voltage to the winding, the only opposition will be the low resistance of the winding. So, if the value of DC voltage is roughly the same as the rated AC voltage, a large value of current would result -high enough to probably burn out the winding.

Since Transformers work on the principle of mutual induction, a fluctuating magnetic field is necessary to induce a voltage into the secondary winding. Since a fluctuating magnetic field requires a fluctuating current, a transformer will only work if an AC voltage is applied to its primary winding.

So, not only will a transformer not work when a DC voltage is applied to its primary winding, it will probably burn out the primary winding.

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In a transformer what induces a current in the secondary coil?

The current flowing in the primary generates a magnetic field which induces a current in the secondary winding.AnswerNo current is induced into the secondary winding of a transformer. What is induced is voltage. Current will only flow in the secondary winding if it is connected to the load, and it is the load that determines the current, not the primary current.


How many amps does a 3 kva transformer draw?

The primary current of a transformer depends upon the secondary current which, in turn, depends upon the load supplied by the transformer. There is not enough information in the question to determine the rated primary and secondary currents of the transformer.


What is the difference between a secondary and primary coil?

The primary coil is the one with voltage applied, or the 'input'. The secondary coil is the one in which a voltage is induced by electromagnetism, or the 'output'. In a step up transformer, the secondary coil voltage is higher than the primary. In a step down transformer, the secondary coil voltage is lower than the primary. In an isolation transformer, the secondary coil voltage is the same as the primary. Here, the point of the transformer isn't to raise or lower voltage, but to keep a particular circuit electrically disconnected from another circuit, while still allowing the circuits to function together (through electromagnetism).


What are the primary winding and secondary winding of a transformer?

The primary winding is the winding connected to the supply, while the secondary winding is the winding connected to the load. The terms, 'primary' and 'secondary' are unrelated to voltage levels.


What happen if the number of loops in the primary and secondary coils in a transformer are the same?

If the number of turns in the primary is the same as the secondary, this would be an isolation transformer. Primary and secondary voltages should match (minus the inherent transformer losses), as should the current.

Related Questions

What is the voltage of the secondary coil when the primary coil is 1200 volts?

You cannot determine the voltage induced into the secondary winding of a transformer unless you know its turns ratio. In other words, you haven't supplied sufficient information to answer the question.


In a transformer what induces a current in the secondary coil?

The current flowing in the primary generates a magnetic field which induces a current in the secondary winding.AnswerNo current is induced into the secondary winding of a transformer. What is induced is voltage. Current will only flow in the secondary winding if it is connected to the load, and it is the load that determines the current, not the primary current.


If the primary winding of a double wound transformer is supplied with the direct current its iron core will become magnetized but there will be no emf induced in the secondary winding?

BECAUSE YOU NEED AC EFFECT TO INDUCE EMF IN TO SECONDARY WINDING.OR DC PULSING.


What is an autotransformer?

An autotransformer is a transformer where the primary and secondary are a single winding.


How many amps does a 3 kva transformer draw?

The primary current of a transformer depends upon the secondary current which, in turn, depends upon the load supplied by the transformer. There is not enough information in the question to determine the rated primary and secondary currents of the transformer.


When can be current in a primary coil induce a current in a secondary coil?

Secondary current = Primary current *(Number of secondary turns /Number of primary) turnsAnswerA current isn't 'induced' into the secondary winding of a transformer. It's a voltage that is induced into the secondary winding.Provided the secondary winding is connected to a load, the secondary voltage then supplies a secondary current which is determined from (Is = Vs/Rload). The primary current then depends upon the value of the secondary current and the turns ratio.


Why phase displacement is maintained between primary and secondary windings of the transformer?

Maintaining a phase displacement between the primary and secondary windings of a transformer allows for the effective transfer of power from the primary to the secondary circuit. This phase difference ensures that the magnetic flux induced in the primary winding can generate a voltage in the secondary winding, enabling power to be transmitted efficiently and accurately between the two circuits.


What are the two coils in a transformer?

primary and secondary coilsAnswerPrimary and secondary windings.


What is the difference between a secondary and primary coil?

The primary coil is the one with voltage applied, or the 'input'. The secondary coil is the one in which a voltage is induced by electromagnetism, or the 'output'. In a step up transformer, the secondary coil voltage is higher than the primary. In a step down transformer, the secondary coil voltage is lower than the primary. In an isolation transformer, the secondary coil voltage is the same as the primary. Here, the point of the transformer isn't to raise or lower voltage, but to keep a particular circuit electrically disconnected from another circuit, while still allowing the circuits to function together (through electromagnetism).


What are the primary winding and secondary winding of a transformer?

The primary winding is the winding connected to the supply, while the secondary winding is the winding connected to the load. The terms, 'primary' and 'secondary' are unrelated to voltage levels.


What happen if the number of loops in the primary and secondary coils in a transformer are the same?

If the number of turns in the primary is the same as the secondary, this would be an isolation transformer. Primary and secondary voltages should match (minus the inherent transformer losses), as should the current.


Why does a transformer need continuous rise and fall of current to induce a current into the secondary windings?

That is how inductance works. The rise is needed to charge the primary. When the field collapses, that is when the current is induced in the secondary winding(s).