Development of SF6 decomposition gas sensor

Gas sensors for detecting SF6 decomposition products have been pursued as low-cost instrumentation for detecting and locating faults in gas-insulated switchgear (GIS). We have developed an amperometric solid-state ionic sensor using fluorine ion-conductive solid electrolyte. In order to improve its sensitivity, the surfaces of the electrolyte are roughened by sandblasting, and are covered with the gas permeable Au electrodes. The roughness of the surfaces and the thickness of the electrodes are optimized. It has been confirmed that the sensor responds promptly to 1 ppm HF gas at room temperature, and returns to its original level once the HF gas is removed.