The RDO PRO-X Dissolved Oxygen Probe uses optical technology (EPA-approved RDO technology for Clean Water Act programs) to measure dissolved oxygen and temperature in demanding process environments. This durable probe requires no calibration or conditioning prior to deployment and does not use membranes. The replaceable RDO Smart Sensor Cap stores calibration coefficients for automatic, error-free setup.

Use flexible communication protocols (4-20 mA, Modbus/RS485, or SDI-12) and easily integrate with PLC systems, telemetry systems and/or HydroVu Data services for real-time feedback within your system.

With the RDO PRO-X, NPDES permit holders can monitor influent, effluent and treatment processes and respond quickly to oxygen and temperature changes for more accurate and efficient process control.

Note: In-Situ partners with leading companies on innovative solutions for DO monitoring in a wide range of applications such as laboratory applications, semi-conductor process monitoring, aquatic transport, and more.


Patented RDO® Technology

EPA-approved optical RDO method makes Dissolved Oxygen sensors easy to use, with a multilayer, abrasion-resistant formulation, a smart cap that carries calibration onboard, and instant hydration to eliminate the need for conditioning prior to use.

Smart Sensor Cap

RDO sensing foils are calibrated at 90 discrete points, and the coefficients are stored in the replaceable cap. Simply press it on and you’re ready to go, no data entry or extra steps needed.

Abrasion Resistance

A unique, three-layer system provides unmatched chemical and abrasion resistance, extending the life of the sensor cap and expanding the range of compatible conditions.

Instant Hydration Conditioning

Unlike other DO sensors, the RDO formulation doesn’t require 12-24 hours of hydration conditioning and reads accurately within 90 seconds of going from dry to wet conditions.

Smart Addressing

All RDO instruments have an easy-to-configure Modbus interface, so they’re ready for integration into another system and access to data is reliable.


Pond Aquaculture

Monitor dissolved oxygen and control aerator function to protect stocks and increase yields.

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Collect accurate process chemistry measurements and water monitoring data to ensure system optimization and compliance.

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