Prototype – Gas density sensor

Monitoring the composition of your gas mixture leads to better controlled processes, saves money, and ensures quality. With this in mind, TrueDyne Sensors AG is rethinking gas density sensors to provide you with a precise and cost-effective tool in order to achieve this. Based on resonating microstructures, our latest innovative prototype combines precision and robustness with a small form factor.


Advantages and applications


Precision at your finger tips


Microstructures vibrating in resonance form the basis for the measurement modules of the TrueDyne Sensors AG in Reinach, Switzerland. Through interaction with the surroundings, vibration characteristics such as resonance frequency and vibration quality of the structures change. Using physical models, the density of gases can be determined from these parameters. The diverse application possibilities of the measuring devices include the monitoring of gas quality / composition of binary mixtures.

Density sensor for gas – technical specification

  • Accuracy: 0.2 to 0.5% of gas composition @ 0.5…6 bar gauge (depending on molar mass difference)
  • Measured variables: Concentration, Density, Temperature, Pressure, Relative humidity (optional)
  • Temperature: -20 °C to 60 °C
  • Pressure range: <10bar
  • Certificats: non-Ex, CE, (Ex Zone tbd)
  • Possible mixtures: all mixtures except: Ar/CO2, C2H4/C2H2, N2/O2 and other mixtures with similar molar mass

Technical background


By knowing the density, pressure, and temperature, the composition of a welding gas can be calculated based on physical models. The difference in molar mass [g/mol] of the two gases is used to measure the gas composition. The more similar the molar mass, the lower the accuracy.


  • Compact design
  • Low-maintenance operation
  • Real-time monitoring
  • Attractive price range
  • Insertion design

Online request


Do you have an application in mind? We look forward hearing from you (e-mail or online request)