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Current transformers (CT) :

  • Current transformer (CT) actually step down the high current to low current for the operation of relays.
  • Current transformer is use for measurement of alternating current (AC).
  • When current is very high then we use current transformer.
  • Current transformer is use for monitoring current .
  • When we use current transformer with potential (voltage) transformer then it is known as instrumentation transformer.
  • Current transformer (CT) is also useful for isolating instruments from high voltage.

This is about current transformer (CT).


Potential (voltage) transformer :

  • Potential transformer is also known as voltage transformer.
  • The principle of potential transformer is similar to current transformer.
  • Potential transformer is the step down transformer which step down voltage.
  • Potential transformer may also use for monitoring voltage.
  • The low voltage output of potential transformer can be use for relay.

This is about potential transformer.
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Their use in protective system?? Not general use
Yeah, for lowering of voltage and current for operation of relay. Relay are use for protective system.

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