ENDRESS+HAUSER  COS51D-AS800

The continuous measurement of the dissolved oxygen concentration is very important in many areas of water management:

• Sewage treatment plants:Oxygen measurement and regulation in the activated sludge basin for a highly efficient biological cleaning process
• Water monitoring: Oxygen measurement in rivers, lakes or seas as an indicator of the water quality
• Water treatment: Oxygen measurement for status monitoring of drinking water for example (oxygen enrichment, corrosion protection etc.)
• Fish farming: Oxygen measurement and regulation for optimum living and growth conditions

• Sensor with digital data transmission:
  • Storage of calibration data in sensor
  • Insensitive to electromagnetic interferences thanks to digital communication to the transmitter
• Maximum measurement accuracy:
  • Longterm-stable measurement thanks to potentiostatic amperometric three-electrode system
  • Long maintenance intervals
  • Intelligent sensor self monitoring
• Membrane covered sensor, i.e.:
  • high O 2 selectivity
  • Minimum maintenance effort
  • Minimum calibration effort thanks to simple calibration in air

• Maximum process safety through contactless inductive signal transmission
• Data safety through digital data transmission
• Easy handling thanks to storage of sensor-specific data in the sensor
• Predictive maintenance possible

The oxygen molecules diffused through the membrane are reduced to hydroxide ions (OH-) at the cathode. Silver is oxidized to silver ions (Ag+) at the anode (this forms a silver halogenide layer).

A current flows due to the electron donation at the cathode and the electron acceptance at the anode. Under constant conditions, this flow is proportional to the oxygen content of the medium.

This current is converted in the transmitter and indicated on the display as an oxygen concentration in mg/l, μg/l, ppm, ppb or Vol%, as a saturation index in % SAT or as an oxygen partial pressure in hPa.