Operation and maintenance of circuit breakers
1） Operation, maintenance, and inspection of Vacuum Circuit Breakers
Conduct maintenance and repair tests on vacuum circuit breakers once a year, and conduct AC power frequency withstand voltage tests on their fracture, overall, and phase to phase connections every two years.
Regularly inspect the vacuum circuit breaker to check for any abnormal sounds or obvious discharge phenomena.
Monitor whether the current and voltage of the circuit where the circuit breaker is located are within the normal range.
Confirm whether the closing (opening) signal light of the circuit breaker, the mechanical indicator of the operating mechanism, the energy storage indicator of the spring operating mechanism, and the position indicator of the handcart are accurate and correct.
After each closing (opening), especially when the relay protection or automatic device action causes the circuit breaker to trip or close, the duty personnel must carefully observe and confirm the actual position of the circuit breaker.
Check the circuit breaker in operation to ensure that the isolation contacts are in place and the moving and stationary contacts are in good contact, while also paying attention to whether there is overheating in the contacts and connection parts.
Keep the switchgear dry and clean, and check for cracks, damage, or discharge marks on the insulation porcelain bottles.
Ensure that the operating mechanism operates flexibly and reliably, and that there are no abnormal phenomena such as breakage or detachment of split pins in the mechanical connection parts.
Check if the fuse of the secondary circuit is intact and undamaged.
2） Operation and Inspection of Sulfur Hexafluoride Circuit Breaker
Similarly, sulfur hexafluoride circuit breakers also need to undergo maintenance and repair tests once a year, and AC power frequency withstand voltage tests on their fracture surface, overall structure, and phases every two years.
Regularly inspect sulfur hexafluoride circuit breakers and pay attention to whether there are any abnormal sounds or obvious discharge phenomena.
Monitor the current and voltage of the circuit where the circuit breaker is located, and observe and confirm its status in the same way as a vacuum circuit breaker after the circuit breaker trips due to a fault or the automatic device is activated.
Pay special attention to whether there is any abnormal odor or leakage sound in the pipeline of the circuit breaker, and record the pressure of sulfur hexafluoride gas to ensure that it is within the normal range of the pressure curve.
(5) During operation, it is necessary to ensure that the isolation contacts are in the correct position, maintain good contact between the moving and stationary contacts, and check whether there is overheating in the contacts and their connecting parts.
(6) The newly installed sulfur hexafluoride circuit breaker must undergo internal gas moisture content and leakage rate testing before being put into use. In addition, these two items should be regularly checked during operation to ensure at least once a year.
(7) If gas needs to be replenished, SF6 gas that meets the standards must be used, and direct discharge of SF6 gas into the atmosphere is strictly prohibited. A specialized recovery device should be used to recover and process the gas.
(8) During operation, constant attention should be paid to changes in the SF6 gas pressure gauge. Once abnormalities are detected, immediate measures should be taken to replenish air or stop operation to ensure the safety and stability of the equipment.
(9) If there is a serious gas leakage or inability to replenish gas in a timely manner, necessary safety measures should be taken quickly to remove the sulfur hexafluoride circuit breaker from operation. When a serious air leak or explosion occurs indoors, the on duty personnel should pay attention to their own safety and activate ventilation equipment to ensure air circulation.