DILO Armaturen und Anlagen GmbH has developed a new GDM test device allowing automatic and reliable testing of gas density monitors.
The newly developed “DensiControl” test devices allow precise, quick and easy verification of switching points in gas density monitors by the given parameters such as pressure and temperature. DILO offers two versions: The DensiControl DA type is suited for GDM testing in dismounted condition, whereas the DensiControl IN version allows automatic verification of switching points in installed condition without having to disassemble the density monitor and without releasing SF6 gas.
The DensiControl devices can be operated via 5.7” colour touch panel and feature user-friendly menu guidance. Fifty different GDM types with their corresponding switching points and up to 200 measurements can be stored. The data can be comfortably saved on USB stick, data output can be effected to establish a test report.
GDM testing in dismounted condition
When GDMs are tested in dismounted condition, the density monitor to be checked is selected in the database and is then installed on the DensiControl device with the aid of a quick clamping mechanism. After starting the measuring process, the pressure is automatically increased to filling pressure and the switching points are activated and recorded automatically. The switching points can be stored in the system with serial number and temperature indication.
Operational GDM testing on site
The new DensiControl IN type, in combination with a specially designed lock valve, allows checking the density monitors in assembled condition, this completely emission-free and without having to release the gas. The GDM to be tested is selected in the database and is separated from the gas compartment through the lock valve. After starting the measuring process, the gas in the density monitor is slowly discharged and stored in the internal vessel of the DensiControl device, the switching points being automatically initiated and recorded. Serial number and temperature data can be stored in the system and are available for later read-out. Once the measuring process is completed, the gas is pumped back into the SF6-filled equipment.
Monitoring of SF6 gas
SF6 is a non-toxic, inert insulating and quenching gas of high dielectric strength and thermal stability. Due to its outstanding properties it is used in enclosed medium and high voltage switchgear as an arc quenching and insulating gas. As SF6 is a major greenhouse gas with high global warming potential listed in the Kyoto protocol it is among the six gases being subject to monitoring. SF6 has to be used in closed systems in order to avoid emissions. Acc. to the latest European F-Gas Regulation 517/2014 gas density monitors have to be checked in regular intervals. With these new developments DILO fully meets today’s requirements in state-of-the-art SF6 gas monitoring.