Simplified maintenance of SF6 switchgear
Professional SF6 gas handling
DILO service carts allow easy and efficient SF6 gas handling on SF6 filled switchgear and equipment with the following functions:
- Recovery of SF6 gas
The gas is recovered from the gas compartment of the switchgear down to the desired final vacuum (mostly 1 mbar).
- Purification and drying
When recovering and filling gas compartments the gas is automatically led in the service cart through dry and particles filters which retain decomposition products, moisture and solid particles effectively. For the reuse of SF6 gas the limit values in accordance with IEC 60480 are to be observed.
- Gas storage
When recovering SF6 from the circuit breaker the gas is stored in gaseous or liquid form by means of a compressor which compresses the gas.
- Evacuation of air or nitrogen
Before filling with SF6 gas the gas compartments must be evacuated in order to avoid mixing with air. Therefore it is evacuated to < 1 mbar with an integrated vacuum pump.
- Filling the gas compartments with SF6
The purified gas is returned into the gas compartment with overpressure or by means of a compressor to the desired operating pressure. The SF6 stored in liquid form is converted into gaseous form via the evaporator installed in the maintenance device.