DGF-I1 Gas Density and Concentration Sensor

Monitor gases and gas mixtures during the process in the smallest of spaces and with minimal quantities of the medium. The sensor not only measures density, but also temperature and pressure – for precise monitoring of product quality and as a basis for determining the concentration of binary gas mixtures.

At the heart of the sensor is a microelectromechanical system (MEMS) with an oscillator in the form of a tuning fork. For the measurement, the metal housing surrounding the MEMS is filled with the medium. The natural frequency of the oscillator varies depending on the density of the gas surrounding it. In order to compensate for temperature effects, a platinum resistor that precisely measures the local temperature is built into the sensor.

The sensor is very compact with a diameter of 33 mm and a length of 63 mm and can be placed in even the smallest of spaces. It is screwed directly into the gas line or the gas tank with the integrated connection, and a filter protects against contamination. The measured values are transmitted to the higher-level system via an RS485 interface. The response time of 5 seconds enables density measurement directly in the process – the measurement does not have to be interrupted.

Measurement Features

  • Density in kg/m³
  • Temperature in °C
  • Pressure in bar absolute
  • Derived measured variables (customer-specific configuration):
  • Concentration of binary gas mixtures, ideal volume percentages (=molar percentages ) in %standard density
  • Average molar mass
  • Customer-specific measured variables
  • Permitted media:
    • Hydrogen (H2)
    • Helium (He)
    • Nitrogen (N2)
    • Oxygen (O2)
    • Carbon dioxide (CO2)
    • Argon (Ar)
    • Media that deviate from the fluids listed above can be used after individual clarification where applicable. These include neon (Ne) and krypton (Kr), for example.