The high voltage vacuum circuit breaker (hereinafter referred to as circuit breaker) is a medium voltage circuit breaker with solid sealed pole insulation as the main conductive circuit, and its operating mechanism adopts VS1 type mechanism. The solid sealed pole structure eliminates the influence of dust and moisture on the outdoor insulation capacity of vacuum arc extinguishing. Circuit breakers are mainly used for AC 50Hz, rated voltage 12kV, 24KV and 40.5KV control and protection in the power grid, widely used in industrial and mining enterprises, substations and other places, and suitable for hot and humid zone products.