The BKM3E series molded case circuit breakers are suitable for AC 50Hz distribution networks with a rated insulation voltage of 1000V, a rated operating voltage up to 400V, and a rated current up to 400A. This series of circuit breakers features overload long-time delay, short-circuit short-time delay, short-circuit instantaneous, over/under voltage, and phase loss protection functions, protecting lines and power supply equipment. It can feed back information such as current, voltage, power, energy, and lifespan to terminal equipment for load detection and monitoring, reducing grid operation and maintenance costs and providing necessary data for future energy efficiency systems. This series of circuit breakers also features automatic identification of distribution network topology and power line carrier communication functions. This series of circuit breakers conforms to the following standards: IEC 60947-1, GB/T 14048.1 "Low-voltage switchgear and controlgear – Part 1: General&qu