Before adding SF6 gas to a breaker, which test must be conducted?

Before adding SF6 gas to a breaker, conducting moisture, purity, and SO2 tests with a hygrometer is essential. This is crucial because SF6 gas is a highly effective insulating and arc-extinguishing medium, but its performance can be severely impacted by contamination.

Moisture can lead to the formation of acids within the gas, which can degrade insulation properties and potentially cause failure. Purity tests ensure that the gas meets the required standards and is free from impurities that could affect its performance. Additionally, measuring sulfur dioxide (SO2) concentrations is important, as elevated levels can indicate chemical breakdown of the SF6 gas, which can compromise its effectiveness.

By ensuring that these parameters are within acceptable limits before introducing the gas into the breaker, safety and operational efficiency are maintained, prolonging the life of the equipment and enhancing reliability in operation.