When commonly used small circuit breakers break circuits, mechanical methods are used to separate the moving contacts and fixed contacts of the small circuit breaker. When closing, the opposite mechanical motion is used to close the moving contact and the fixed contact. During the operation of connecting and disconnecting the load circuit, an arc will occur between the fixed contact and the moving contact. The arc generated during the disconnection process is much more severe than that during the closing process. When the breaking current is large, especially when breaking a short circuit, the arc is very large, and it is often very difficult to break the circuit