Oil Immersed circuit Breaker

The low voltage circuit breaker is the central component of CSP Technology. Circuit breaker provides the entire over current, over load, fault current, earth fault protection to the transformer.

  • Tamper Proof
  • Lowest Total Cost of Ownership
  • Thermal Protection by Tracking Oil Temperature
  • Higher Transformer availability
  • Easier and Simpler Installation
  • Safer Operation
  • Automatic Load Management





  • Thermal Tripping : The critical thermal modeling of the transformer by the Oil immersed Circuit breaker is accomplished because of the Bi-metallic strips which respond thermally to the transformer oil and also to the temperature changes created by the flow of Load currents in them.
  • Magnetic Tripping :Magnetic trip element increases the opening speed of the circuit breaker under high fault current conditions. This increased opening speed permits the circuitbreaker to interrupt larger values of fault currents.

Completely self  protected (CSP)

  • CSP is a protection system for distribution transformers.  The CSP protection system protects the transformer from lightning, secondary faults, severe overloads and provides
    visual warning of abnormal loading conditions. CSP Technology allows transformer manufacturers to build high
    performance distribution transformers which mitigate the operation and maintenance problems associated with conventional transformers.
  • CSP design provides maximum protection against transformer failure and disruptive
    outages. It also protects you from extra costs of more complicated installation, unnecessary equipment and power downtime.

Components of CSP

  • Internal Oil Immersed Circuit Breaker:
    Provides secondary fault and overload
    protection.  The circuit breaker is mounted inside of the transformer and it is connected between the secondary
    winding and secondary bushing, such that the current flows through the circuit breaker.
  • Load Management Signal Light :
    Provides visual indication of abnormal loading conditions.  The signal light is mounted on the exterior wall of the transformer tank near the operating handle of the circuit breaker.  The signal light is electrically connected to the signal light sensing circuit within the transformer.
  • Operating Handle:
    Resetting Mechanism And operate the breaker.
  • HT Fuse :
    Acts as over current protection by isolating the faulty transformer from the network.  It is mounted inside of the transformer and it is connected between the incoming high voltage lead from the bushing and the
    high voltage line lead from the transformer primary winding.

Emergency Control

  • Emergency control allows the power utility to immediately restore service in an emergency by closing the circuit breaker even when the preset overloading limit is reached.

Breaker on Bracket (BOB)

  • Breaker on Bracket design allows simple and fast installation of the circuit breaker. Significantly reduces  any issues borne out of incorrect installation of the circuit breaker.