CARBOTEC NIR is a very precise, optical carbon dioxide sensor for measurement of dissolved CO2 in water (e. g. for conductivity control) or in fermentation reactors. The CO2 content can give an indication of the progress of a fermentation reaction.


For continuous measurement of dissolved carbon dioxide in liquids, CARBOTEC NIR is perfectly suited. The instrument is designed for applications requiring maximum sensitivity and highest accuracy. It is easy to operate and almost maintenance-free. The new generation of CARBOTEC NIR sensors is based on Attenuated Total Reflection (ATR) technology. Near infrared (NIR) light is transmitted through a sapphire crystal. The NIR light reflects several times on the inner surfaces of the crystal, while the outer surfaces are in contact with the carbonated liquid. Since CO2 molecules absorb the specific wavelength of the transmitted light, each reflection decreases the intensity according to the CO2 content in the product. The sensor provides the “true” carbon dioxide content, as quantified by the NIR absorption. The measurement result is neither influenced by other gases in the product not by its colour, turbidity and viscosity. Due to the absence of moving parts, the instrument is virtually maintenance-free. Any temperature drifts of the measured signal are automatically compensated for by an internal Pt100 sensor.

  • Optical technology based on Attenuated Total Reflection (ATR)
  • Determination of “true” carbon dioxide content not influenced by other gases
  • Short response time and excellent long-term stability
  • Highly accurate and virtually maintenance-free
  • Various flange connections available
  • Hygienic execution and full CIP capability

Technical Data

Measuring Range 0 - 10 g/l
Accuracy ± 0,1 g/l
Repeatability ± 0,02 g/l
Response Time ≤ 3 s
Pressure of Operation max. 10 bar
Temperature of Operation - 10 - + 85 °C
Temperature Sensor Pt100
Material 1.4404/AISI 316L, sapphire glass, EPDM (FDA), PTFE (FDA)
Connections compatible to Varivent© inline-housings DN65 - DN150; others on request
Input 6 x digital (24 VDC)
Output 3 x digital (24 VDC) & 2 x analog (4 - 20 mA)
Profibus DP option
Enclosure Rating IP65
Power Supply 24 VDC


Tel.: +49 6181 18 78 0
Fax: +49 6181 18 78 50


CARBOTEC NIR - Datasheet / Datenblatt
(0,46 MB, PDF, EN/DE)