The switch disconnector is using SF6 as extinguishing and insulating medium. The epoxy resin housing is equipped with two thermo plastic windows to allow visual inspection.
The SFG has 3 positions: CLOSE-OPEN-EARTHING. Mechanical endurance is 5000 C/O and 1000 O/Earth.
Each switch is sealed for life (i.e. 30 years) and maintenance free. SF6 gas pressure is 1.4 bar and the SFG switch incorporates a capacitive divider for voltage indication.