Dissolved Oxygen (DO) Sensor
Measuring oxygen availability in liquids to sustain biological processes and control reactions.
What Does a Dissolved Oxygen Sensor Measure?
A dissolved oxygen (DO) sensor measures the amount of oxygen dissolved in a liquid, typically expressed in mg/L or ppm. Dissolved oxygen is a critical parameter for biological treatment, aquatic life sustainability, corrosion control, and overall water quality.
Working Principle
DO sensors operate by detecting oxygen diffusion from a liquid into a sensing element. The sensor converts the oxygen concentration into an electrical signal proportional to DO levels.
- Electrochemical (membrane-covered amperometric)
- Optical (luminescence quenching)
- Oxygen diffusion through selective membranes
Common Types of Dissolved Oxygen Sensors
- Electrochemical DO Sensors
- Optical (Luminescent) DO Sensors
- Inline DO Probes
- Submersible DO Sensors
- Portable DO Meters
Signals & Outputs
- Analog: 4–20 mA
- Digital: RS-485 (Modbus RTU), HART
- Fieldbus & Industrial Ethernet (via analyzers)
- Measured in mg/L (ppm) and % saturation
Sensor Cluster
This sensor belongs to the Process Quality Cluster, focusing on biological process health, aeration efficiency, organic load control, and regulatory compliance.
Direct & Indirect Meaning of DO Data
Direct Meaning
The measured value directly represents the concentration of oxygen dissolved in a liquid.
Indirect Meaning
DO trends indirectly indicate biological activity health, aeration efficiency, organic load balance, corrosion potential, and the risk of anaerobic conditions.
Industries Using Dissolved Oxygen Sensors
Role of IoT in Dissolved Oxygen Monitoring
With Industrial IoT integration, DO sensors enable real-time aeration control, early detection of biological process failures, energy optimization, and compliance-ready water quality reporting.
IndustrioPedia Perspective
The Dissolved Oxygen Sensor is a lifeline for biological systems. By ensuring adequate oxygen availability, it sustains treatment efficiency, protects ecosystems, and stabilizes industrial water processes.