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When the secondary of a transformer is opened, there is no longer any load on the transformer. There will be some current flowing in the primary winding, which is needed to induce the voltage in the secondary. This primary current is referred to as the "no load" current, and is indicative of the core losses in the transformer.

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Q: What is the function of the primary current when the secondary winding of the transformer is open?
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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 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.


What is the current in the secondary coil fi the current in the primary coil is 5.0A 10 loops on primary coil and 20 on secondary coil?

If I am not wrong then you have asked about a transformer. And its a current transformer. By theory of voltage transformer we know that Vs/Vp = Ns/Np So for answering your question we need the value of number of turns in primary and secondary coil. But you can use this equation to find your answer if you have other values. By using ohmic law you can convert voltage to current.


A transformer has a primary volt of 240v and a secondary volt of 48v what is the turn ratio?

3

Related questions

When secondary coil is open there is no current in the primary coil WHY?

I am assuming the question is about the power / distribution transformer and not the current transformer. The primary current is a function of load connected on secondary. With the open secondary, there is no load, no current, it is open circuit. Hence no primary current. However there is always some small amount of no load current in the primary winding.


Does a transformer increase amps?

The primary current is determined by the secondary current, not the other way around. For example, a step up transformer will step up the primary voltage in proportion to the turns ratio of the transformer. Any secondary current is then determined by the secondary voltage and the load, NOT by the primary current. The primary current is then determined by the secondary current in proportion to the reciprocal of the turns ratio.


What is the current in the secondary coil if current in primary is 5.0A?

It depends on the turns ratio between the primary and the secondary. If the ratio were 10:1, a step-down transformer, for instance, the current in the secondary would be about 50A. If it were 1:10, a step-up transformer, however, the current in the secondary would be about 0.5A.AnswerThe primary current doesn't determine the secondary current. The secondary current is entirely-dependent on the secondary voltage and the impedance of the load. It is this secondary current that the determines the primary current. So you should be asking, "What value of secondary current would result in a primary current of 5.0 A?"


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 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.


When 440 volts and 300 amps is given as an input to the transformer the output obtained is 11 kva in this secondary current will decrease or not?

Your question reveals a misunderstanding of how a transformer works.The primary current of a transformer is determined by the secondary current, not the other way around. When the secondary voltage is applied to a load, a secondary current flows, and its value is determined by the secondary voltage and the load impedance. This secondary current then determines the value of the primary current.


How do you calculate current on the primary side of a transformer only knowing the turns ratio and the voltage ratio?

The primary current on a loaded transformer depends on the secondary current, which is determined by the load. So, if you know the secondary load current, then you can use the turns ratio of the transformer to determine the primary current:Ip/Is = Ns/Np


Why primary current is higher than secondary current in transformer with turns ratio 1?

In a transformer with a turns ratio equal to 1, the primary current comprises the reflected secondary current plus the magnetizing current necessary to sustain the "back EMF developed across the mutual inductance coupling the primary winding to the secondary. Therefore the primary current is always greater than the secondary current in a transformer with a turns ratio equal to 1. This should be evident by applying Kirchhoff's Current Law to the central node of the "T-equivalent" model of a transformer.


How do you calculate current flow transformer when 240 Vrms is supply?

The secondary current of a transformer is determined by the load and the secondary voltage applied to that load, and this, in turn, will determine the primary current by the inverse of the turns ratio. However, if you are asking about a transformer's rated secondary and primary currents, then you need to divide the transformer's apparent power rating (expressed in volt amperes) by the rated secondary and primary voltages respectively.


What is the current in the secondary coil fi the current in the primary coil is 5.0A 10 loops on primary coil and 20 on secondary coil?

If I am not wrong then you have asked about a transformer. And its a current transformer. By theory of voltage transformer we know that Vs/Vp = Ns/Np So for answering your question we need the value of number of turns in primary and secondary coil. But you can use this equation to find your answer if you have other values. By using ohmic law you can convert voltage to current.


What in a transformer determines whether it increases or reduces current?

The ratio of the primary winding turns to the secondary winding turns. This governs voltage which is directly related to the current and load.AnswerA transformer increases or decreases voltage, notcurrent. The secondary current is determined by the load, and the secondary current determines the primary current. If there is no load, then there is no secondary current, and the primary current is mainly made up of the magnetising current.