With the rapid development of China's electric power industry, when the reclosing operation was proposed in the 1970s to the 1980s, the time required for the contact to close the second contact was defined as "golden short time". In order to ensure the breaking capacity of the second "part" in the reclosing, according to the power industry standard DL/T755 "Guidelines for the safety and stability of the power system", the high voltage circuit breaker should have a short time of no more than 60ms, and 40~55ms is recommended, which can make the working condition of the arc extinguishing chamber have sufficient time to change from the closing process to the state required before the opening. The State grid requires the circuit breaker to take reliable measures to achieve the short time by the circuit breaker itself, the high-voltage circuit breaker, closing instructions are issued by the auxiliary switch configured by its operating mechanism, so the auxiliary switch is an ideal and reliable mechanism for short time control.
The switch takes FK switch as the body, inherits the advantages of FK switch, such as large rated current, strong breaking ability, flexible contact Angle, high temperature resistance, etc. At the same time, the delay function module with mechanical structure is cleverly designed, no power supply is required, the action is flexible and reliable, and the delay time is accurate.