News Details

I. Purpose and Significance of the Test

    If the moisture content in SF6 gas is excessive in SF6 electrical equipment, it can cause moisture to condense on the surface of insulating components, reducing insulation strength. Moreover, when SF6 mixes with water under the action of an arc, it produces toxic and corrosive substances that corrode the internal structure of the electrical equipment. Therefore, regulations require SF6 micro-water content (also called humidity) testing to ensure that the moisture content is within the required range.

II. Test Procedure

1. According to the gas outlet of the SF6 equipment under test, select an appropriate adapter joint, and use the configured gas tube to connect the gas outlet of the SF6 equipment to the gas inlet of the instrument. The gas outlet should be directed to the downwind direction through the outlet tube, or use a dedicated device to collect the exhaust gas.

2. Connect the power supply, rotate the "Protect-Measure" handle on the instrument panel to the "Measure" position, adjust the flow adjustment knob to set the inlet gas flow to about 0.6L/min, and start the measurement.

3. Since there is residual gas in the instrument, the humidity value (ppm) will be relatively large at the beginning of the measurement. As SF6 gas flows in, the humidity value will gradually decrease. Generally, after two to three minutes, the humidity value will stabilize, and this value is the micro-water content of the SF6 gas.

4. After the test is completed, remove the adapter joint and the gas tube, turn off the instrument power, and rotate the "Protect-Measure" handle on the instrument panel to the "Protect" position.

III. Precautions

1. The inlet tube and the nut joint of the SF6 equipment should be tightened with a wrench through the configured joint. If necessary, wrap the configured sealing tape around the joint threads a few turns to ensure no gas leakage.

2. When adjusting the gas flow, the flow valve should be opened slowly so that the flow indication is around 0.6L/min, and the flow should be stabilized at this value for measurement.

3. When the instrument is not in use, the "Protect-Measure" handle must be rotated to the "Protect" position; otherwise, the high-precision dew point sensor will be exposed to a high-humidity environment, causing sensor failure.

4. The humidity measured by the instrument is in ppm, i.e., μL/L. According to the "Regulations for Preventive Tests of Power Equipment", for circuit breakers after overhaul, the arc extinguishing chamber gas compartment should be less than 150μL/L, and other gas compartments should be less than 250μL/L; for circuit breakers in operation, the arc extinguishing chamber gas compartment should be less than 300μL/L, and other gas compartments should be less than 500μL/L.

Tuozhipu Electric's main equipment:

    Variable frequency series resonance test device, DC high voltage generator, SF6 gas micro-water meter, SF6 gas leak detector, SF6 gas purity tester, SF6 gas comprehensive tester, SF6 density relay calibrator, test transformer (power frequency withstand voltage test device), variable frequency anti-interference high voltage dielectric loss tester, triple frequency generator (induction withstand voltage test device), frequency multiplier generator set, AC/DC voltage divider (high voltage measuring instrument), high current generator (current booster), transformer DC resistance tester, transformer turns ratio tester, transformer capacity characteristic tester, transformer no-load short-circuit tester, transformer on-load tap changer tester, transformer winding deformation tester, transformer characteristic comprehensive test bench, transformer core grounding current tester, microcomputer relay protection tester, instrument transformer characteristic comprehensive tester, high voltage switch mechanical characteristic tester (circuit breaker characteristic tester), loop resistance tester (contact resistance tester), zinc oxide arrester tester, transmission line parameter tester, capacitance and inductance tester, grounding resistance tester, insulation resistance tester (megohmmeter), insulation oil dielectric strength tester (insulation oil withstand voltage tester), insulation oil chromatograph, insulation boots (gloves) withstand voltage test device, power safety tools test equipment, battery constant current discharge tester, mining cable fault tester, vacuum oil filter, mining detection equipment, oil analysis instruments, intelligent solar photovoltaic junction box tester, electric heating appliances, insulation products, etc.