Molded case circuit breaker with primary and secondary line isolation

The utility model relates to a moulded case circuit breaker with primary and secondary line isolation, which comprises a base, a middle cover, a first upper cover and a second upper cover, the middle cover covers the base, the bottom of the base is provided with a bottom plate, one side of the middle cover is provided with a circuit board, the other side of the middle cover is provided with an interface board, and the circuit board is provided with a backup power supply module and a protection module respectively. The interface board is provided with a measurement module, the first upper cover covers the backup power supply module and the protection module, and the second upper cover covers the measurement module. According to the utility model, the circuit board and the interface board are arranged on the middle cover, so that the circuit board and the main loop copper bar are respectively placed in two independent spaces, and compared with the same-space placement of the existing molded case circuit breaker