LV Breaker

Completely self protected “CSP” transformers contain safeguards to avoid issues that would cause overloading or damage to the transformer. Conventional transformers do not have any of these features which usually means they will need to be attached to a cut out switch.

There are several CSP components such as the lighting arrester, current sensing link and the low voltage breaker.

Sei makes a CSP low voltage breaker designed for high performance distribution transformers.

The CSP system protects the transformers from lightning, secondary faults, severe overloads and provides visual warning for abnormal loading conditions.

  • Sei makes several CSP components that, when applied, provide multiple layers of protection. Our CSP components have been type tested to IEC Std. 60947-2.
    High Voltage Fuse
  • Provide 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.
    Low Voltage Fuse Secondary Circuit Breaker
  • Provides secondary fault and overload protection. The LV 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.
    Overload Indicator
  • Provides visual indication for 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.
    Sei’s CSP Advantages
  • Tamper Proof / Lowest Total Cost of Ownership / Thermal Protection by Tracking Oil Temperature / Higher Transformer availability / Easier and Simpler Installation / Safer Operation / More Reliable Service / Automatic Load Management / Better Aesthetics
    Optional Features
  • Magnetic Trip

    Increases opening speed of the circuit breaker under high fault current conditions.

  • 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

    Allows simple and fast installation of the circuit breaker.

  • Signal light

    Provides early warning of overload/high oil temperatures.