The high-voltage circuit breaker is a high-voltage switchgear with a powerful arc extinguishing device, and is an important switchgear in the power supply and distribution system. Its text conforms to QF. The high-voltage circuit breaker can not only open and close the normal line and the fault line, but also can connect and bear the short-circuit current for a certain period of time, and can automatically trip under the action of the protection device to remove the short-circuit fault.