BM-50L series miniature residual current circuit breaker is suitable for AC 50 Hz, rated voltage to 230 V / 400 V, rated current to 50 a power supply lines, to protect lines and electrical equipment overload and short circuit. Leakage circuit breaker is used for leakage protection, and its leakage tripping mode is electronic, which is mainly composed of zero sequence current transformer, electronic component board and circuit breaker.