VDF-32/40/63 is a kind of circuit breaker with complete update of residual current detection, based on current type A RCBB. It can not only effective protect AC and pulsing DC (B 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.