dissolved CO2 probe

  • Dissolved CO2 ProbeIdeal for industrial and shallow water applications
  • Water quality and wastewater industries
  • Aquaculture
  • Scientific research

The ES-CO2 is a new membrane covered optical CO2 sensor for monitoring dissolved CO2 online.

The ES-CO2 is our most popular dissolved CO2 sensor as it is low cost, robust, accurate, has a moderate depth rating (1000m), and can be easily integrated into existing data acquisition systems and PLC’s.

The ES-CO2 is delivered to you pre-calibrated and ready to deploy. The calibration lasts approximately 12 months. Therefore, the ES-CO2 is a low maintenance sensor.


more details

The measurement of dissolved carbon dioxide in water is one of the most important parameters for water monitoring. Our engineers have developed a new membrane covered optical CO2 sensor with titanium housing and other improved characteristics. So the new dissolved CO2 sensor is designed for depths of up to 1,000 m, has an analogue or digital output, a reduced current uptake and includes an automatic internal temperature compensation. The sensor is designed to be interfaced externally to CTD probe systems, to own measuring systems or as stand alone sensor.


measurement principle

The inner sensor volume is separated from the sample by means of a gas permeable silicone membrane. Liquids and solids are not able to pass the membrane. If the sensor is dived into a sample, the CO2 partial pressure equalisation is achieved between the inner sensor volume and the sample. Inside the sensor there is an optical sensor mounted. It’s working principle is based on the Single-Beam Dual Wavelength NDIR. This measurement of the CO2 partial pressure has to be accompanied by the measurement of the temperature in the water and by the air pressure for calculating the carbon dioxide concentration.


  • submersible direct reading sensor for natural and industrial waters and sea water;
  • detects CO2 and total inorganic carbon when measuring additionally pH;
  • no signal interference to silicate, phosphate, HCO3- and CO32-;
  • built-in reference measurement for superior stability;
  • calibration coefficients stored internally;
  • for depths of up to 1,000 m;
  • less than 0.5 W power consumption;
  • with analogue or digital output (please select);
  • with internal temperature compensation;
  • compensation of humidity and other influences;
  • heated sensor head to avoid condensation


brochures and manual


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