Current Transformer (CT) – Construction and Working Principle

Applications of a Potential Transformer

The applications of a potential transformer are listed below:

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  Used in metering and relay circuits
  
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  Uses in power line carrier communication networks
  
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  Used in protection devices electrically
  
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  Used for the protection of impedance in different applications like the generators
  
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  Used for protecting feeders
  
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  Used as protection voltage transformers
  
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  Used in synchronization of feeders and generators
  

Advantages of a Potential Transformer

The advantages of a potential transformer are summarized below:

• 
  Ammeter and voltmeter can be connected to control high current and voltage, respectively.
  
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  Irrespective of the sensing of voltage or current, the level of the low range meter can be configured with the help of a potential transformer.
  
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  The operation of these instruments is utilized for working in many forms of protecting devices such as the relays and pilot lights.
  
• 
  A single potential transformer can be used to control several instruments.
  

Disadvantages of a Potential Transformer

Due to the efficiency of the device, there are not several drawbacks. The main disadvantage of a potential transformer is that it holds this configuration limited to only AC networks and cannot be used on the DC circuits.

Conclusion

The potential transformers are mainly employed in the protecting relaying system since the potential windings of the protective instrument are not directly connected to the network in the case of the high voltage. As a result, it is essential to step down the input voltage and also to insulate the protective system from the primary network.