High & Medium Voltage switchgear is very reliable and low maintenance provided, it is able to operate within specified parameters. The use of SF6 as quenching gas is extremely important to guarantee safe operation during the life of equipment. If moisture inside the gas exceeds critical limits, problems can occur.
When SF6 and moisture are exposed to high amounts of heat, such as equipment operating under load or fault current, decomposition by-products can form and cause damage to the switchgear. By products also pose health risks to personnel, should exposure occur. Once internal desiccants have saturated, moisture levels will rise.
If there is no need to enter the switchgear otherwise, external desiccants can be used to reduce high moisture levels and maintain levels below the manufacturer’s specified limits. Best of all, when the desiccants inside the chambers have stopped working, simply replace them. Be sure to follow proper handling and safety procedures in accordance with your company’s guidelines and/or government regulations.