Sulfur hexafluoride gas is colorless, odorless, non-combustible, non-reactive, relatively non-toxic, and suffocating liquefied gas? It is a necessary medium for the normal operation of many types of circuit breakers. Therefore, it is necessary to master the method of SF6 switch gas supply and circuit breaker charging SF6 gas. According to experience, the sulphur hexafluoride switch gas supply should be inflated under the premise of fine weather and good ventilation. Follow the steps below:
Sulfur hexafluoride switch gas supply The first step is to take the sulfur hexafluoride circuit breaker out of operation and ensure safety. Place the SF6 cylinder upright, connect the oxygen pressure reducing valve, and connect the inflation tube to the pressure reducing valve. Open the cylinder valve, and then open the pressure reducing valve to make the low pressure side pressure of 20,000 to 40,000 Pa, then use a copper rod with a diameter of 8 mm to open the valve core of the inflation tube, and deflate for 5 to 10 seconds to flush the pipeline.
The second step of sulphur hexafluoride switch gas supply is to measure the ambient temperature around the circuit breaker. According to the temperature-pressure curve provided by the manufacturer, check the rated pressure of the circuit breaker during inflation. Unscrew the plug under the C-phase transmission box of the circuit breaker, connect the inflation tube, and then slowly open the pressure reducing valve to inflate the circuit breaker. When you hear the sound of inflation in the connecting pipe, it proves that the pressure reducing valve is working normally. When the gas pressure in the circuit breaker is close to the rated pressure, inflate slowly to avoid excessive pressure in the circuit breaker.
When the gas in the circuit breaker is charged to the rated pressure, close the pressure reducing valve, first remove the inflation tube from the circuit breaker interface, and then screw the plug to the interface, and unscrew the connection between the connector and the inflation tube. Close the gas cylinder valve, remove the pressure reducing valve, and store the pressure reducing valve and joints in a dry place for future use.
Sulfur hexafluoride switch gas supply The third step, after the circuit breaker is charged to the rated pressure, all sealing surfaces should be qualitatively checked for leakage. If you find any missing points, you can contact the manufacturer for handling. In addition, check the water content of sulfur hexafluoride gas in the circuit breaker. The moisture measurement should be performed 24 hours after inflating. Use the air-filling port of the circuit breaker to connect the conical needle pressure reducing valve to control the gas flow and measure it with a trace moisture detector. The measured data should be based on the ambient temperature and against the moisture content-temperature curve provided by the manufacturer. The value should not exceed 150 microliters/liter (20 degrees Celsius) during on-site handover, and should not exceed 300 microliters/liter (20 degrees Celsius) during operation.
The fourth step of sulphur hexafluoride switch gas supply is to record the temperature, humidity and sulphur hexafluoride pressure value of the day, and make a mark at the indication of the sulphur hexafluoride pressure gauge for future observation and comparison to determine whether its operating status exists abnormal.