This product is used in distribution panels in North America with a rated current above 1000A, in conjunction with NOARK M6 frame Molded Case Circuit Breakers, to meet the sensitivity requirements for neutral current sensing. It achieves the following functions: 1. Monitoring of neutral current, 2. When there is ground fault current in the system, it forms a zero-sequence current monitoring with the built-in current transformer of the Molded Case Circuit Breaker.