TORD4B-63 is a kind of circuit breaker with complete update of residual current detection, based on current type A RCCB. It can not only effectively protect AC and pulsing DC( A type) , the possible compound residual current (F type ) , but also smoothing DC and high frequency residual current(1K Hz) .In a circuit consisting of rectifier, inverter, frequency inverter, etc, the leakage current caused in DC loop circuit can be effectively detected and protected.