PLASTIC CASE CIRCUIT BREAKER

The invention relates to the field of low-voltage electrical appliances, in particular to a moulded case circuit breaker comprising an circuit breaker body including an operating mechanism, and an electric operating device including a handle drivingly matched with the electric operating device, wherein said electric operating device includes a rotary disk that is rotatably set, a cam and a sliding block that are set on the rotary disk, and a slide rail for limiting and guiding the sliding block, said sliding block includes a driven groove of sliding block and a driving groove of sliding block, the cam is drivingly matched with the driven groove of sliding block, and the handle is inserted in the driving groove of sliding block, the rotary disk rotates and drives the sliding block to reciprocate along the sliding rail through the cam, and the sliding block drives the handle to swing through the driving groove of sliding block driving, so as to switch in/switch off the moulded case circuit breaker. The invention provides a moulded case circuit breaker, the sliding block of which has a simple, firm and reliable structure, and can significantly improve the reliability of the electric operating device.