Vacuum circuit breakers are becoming more and more popular, and safety accidents of misoperation often occur. At present, safety accidents of outdoor vacuum circuit breakers operating online with load pulling and closing knife switches often occur, causing the circuit breaker of the whole machine to burn out, resulting in shutdown, power failure, and even serious hazards of staff burns, so anti-mis-touch operation is very necessary.
When operating the vacuum circuit breaker, the operating staff still use the method of operating the low-oil circuit breaker (the door handle of the trolley of the low-oil circuit breaker is slightly lifted up at the minimum position of the control panel, and the brake will be opened immediately), instead of lifting the door handle of the trolley When it is higher than the level position or equivalent to the level position (the circuit breaker is still in the closing state at this moment), it is sent into the operating position.
The time when the boiler auxiliary equipment in the power plant turns to heat and standby. At this time, the mentality of the operating staff is poor, and the circuit breaker in the maintenance position is incorrectly evaluated without carefully checking the opening and closing indicator (or the indicator is not clearly marked). It must be in the opening state, and it will be sent to the operating position safely.
The door handle of the trolley of the outdoor vacuum circuit breaker is at a higher level (the door handle's level position matches the opening position of the power switch), which leads to short operating staff who mistakenly think that the handle is already at the level position without lifting the handle to the level position. disconnected. The circuit breaker itself lacks the technical measures to avoid the load pulling and closing knife switch, and the manufacturer did not manufacture the circuit breaker of this model and specification in accordance with the regulations in the "Five Preventions".
(1) The vehicle-type vacuum circuit breaker is equipped with a braking system. When the circuit breaker is closed, the moving mechanism of the circuit breaker is locked so that the circuit breaker cannot be moved when the circuit breaker is in the closed state; If the conditions are met, it cannot be sent to the operating position.
(2) Improve the sliding door handle of the circuit breaker to ensure that the circuit breaker will be disconnected reliably as long as the handle of the circuit breaker is extended to a certain extent.
(3) Refit a small alarm system the size of a mobile phone to the handcart vacuum circuit breaker that has been put into use. The specific method is to introduce a switch auxiliary contact of the outdoor vacuum circuit breaker into a microphone socket on the control panel of the circuit breaker. When the operator operates the power switch, he first inserts the power plug of the alarm system into the socket. At this time, the alarm system immediately sends out a creaking hissing sound or a voice broadcast of "the power switch is closed, and operation is strictly prohibited". If the normally closed contact circuit breaker is in the opening state, after the power plug of the alarm system is inserted into the socket, a speaker will sound: "opening is allowed to operate"; if the circuit breaker is in the closing position, after the power plug of the alarm system is inserted into the socket , it is not easy to send out the speaker, and it cannot be operated at this time. In this way, a safety defense is added to the anti-mistouch operation, and it is a simple technical measure to prevent accidental pulling of the knife switch.