Gas density sensor
For gas density, temperature and pressure of insulating gases, with Modbus® or analogue 4 … 20 mA signal
- Permanent monitoring of the relevant gas condition parameters in closed tanks
- For internal and external SF6-insulated equipment
- Density measurement of alternative gases in electrical equipment or in the laboratory
- High-accuracy sensor technology
- Digital Modbus® RTU or analogue 4 … 20 mA output signal
- IP67 ingress protection, optionally with IP6k9k field case
- Very good long-term stability and EMC characteristics
- Compact design
Description of the Gas density sensor
Permanent monitoring
In order to prevent system failures in switchgear and network outages, the permanent monitoring of the gas density is essential.
The model GD-20 calculates the current gas density from the pressure and temperature using a complex virial equation in the gas density sensor´s powerful microprocessor. Pressure changes resulting from thermal effects will be compensated by this and will not affect the output value.
Modbus® fieldbus
The RS-485 interface communicates using the Modbus® RTU protocol. The instrument’s output parameters and their units can be configured and read according to requirements.The GD-20 model can be freely configured at the factory for any defined gas mixture consisting of SF6, N2, CF4, O2, CO2, 3M™ Novec™ 4710, He and Ar.
The calculation is based on the partial pressure method of the individual gas components.
Signal stability
Due to its high long-term stability, the sensor is maintenance-free and requires no recalibration. Due to the hermetically sealed weld seam and a measuring cell design without sealing elements, the permanent sealing of the measuring cell is ensured.
The gas density sensor is also available with analogue output signal (4 … 20 mA) for output of the compensated pressure (p at 20 °C [68 °F]).