SF6 Measurement guide

The quality of the SF₆ is critical in ensuring the performance of gas insulated switchgear, therefore regular monitoring of the gas is importance. Over the last few years a number of instruments have become available that allow on-site testing of the parameters of SF₆ gas, namely SF₆ content, humidity and decomposition products. This brochure seeks to provide practical advice regarding the selection and use of these instruments so as to achieve reliable and consistent results. Guidance is also provided in how to assess the results and identifies potential remedial measures. A detailed discussion is included on the historic frost point temperature limit of -5 °C and how alternative limits may be more appropriate in certain situations.