C45L residual current circuit breaker is used for the protection, against electrical leakage in the circuit of 50Hz (or 60Hz) rated voltage 240V (single-phase) or 240/415V and below (3-phase0, rated current up to 60A. When somebody gets an electric shock or the residual current of the circuit exceeds the fixed value, the R.C.C.B. can cut off the power within the time of 0.1s automatically protecting the personal safety and preventing the equipment from the fault resulted from the residual current. With this function, the R.C.C.B can protect the circuit against over-load and short-circuit or can be used for the unfrequent switchover of the circuit under normal conditions.