Oxygen Sensors & Transmitters

Oxygen Sensors & Transmitters

Dissolved oxygen sensors and transmitters provide continuous measurement of oxygen concentration (or related representations such as % saturation and partial pressure) in liquids and are foundational for quality assurance and process control. Dissolved oxygen is critical in applications such as aeration control, fermentation, and inertization, and the measurement requirement spans from oxygen traces to high concentrations depending on the process and industry.

Endress+Hauser supplies oxygen analysis solutions across measurement ranges and operating conditions, including hygienic processes and hazardous areas. The selection typically balances sensor principle and maintenance expectations: amperometric sensors are positioned for accurate, linear measurement from trace levels to high concentrations but require regular maintenance, while optical sensors are positioned for fast stabilization of measured values and extremely low maintenance.

Amperometric measurement uses a working electrode and counter electrode surrounded by electrolyte and separated from the process by a membrane. A voltage drives the electrochemical reaction: oxygen diffuses through the membrane, is converted to a current at the working electrode, and the resulting current is proportional to oxygen partial pressure in the medium. Optical sensors, including designs featuring a stable fluorescence layer, provide an alternative approach when minimizing maintenance and achieving rapid stable readings is prioritized.

Applications include water and wastewater treatment (notably aeration basins), chemical processing, power, life sciences and pharmaceutical production, food & beverage, and aquaculture/fish farming. In these environments, oxygen measurement supports efficiency (energy optimization in aeration), quality (fermentation control), and safety (inertization and oxygen limitation strategies), with installation tailored to the hydraulic and hygienic requirements of each process.

System implementation typically pairs the sensor with an appropriate transmitter and mounting assembly to ensure representative exposure, stable temperature/pressure compensation, and serviceability. Where multiparameter platforms are used, oxygen measurement can be combined with complementary liquid-analysis signals (for example pH, conductivity, turbidity) to improve interpretability and reduce the risk of single-parameter control bias.

At Eastern Controls, We are proud to be the exclusive authorized sales and service representative for Endress+Hauser.