ClO2-100 Chlorine Dioxide Sensor

Overview

The ClO2-100 is an advanced sensor specifically designed for measuring chlorine dioxide (ClO2) concentration in water. Chlorine dioxide is an increasingly popular alternative disinfectant to chlorine, offering superior oxidation power without producing harmful trihalomethanes (THMs). This sensor is essential for drinking water treatment plants, food processing facilities, and industrial applications.

Key Features

• Selective Detection: Specifically measures ClO2 without interference from chlorine
• Wide Range: Measures from 0.01 to 20.00 mg/L (ppm)
• Digital Output: RS485 Modbus RTU for seamless integration with SCADA and IoT systems
• Fast Response: Results within 60 seconds
• Automatic Temperature Compensation: Integrated PT1000 sensor for accurate readings
• Direct Connection: Connect directly to computer or PLC without additional instrumentation
• High Protection: IP68 waterproof rating ensures reliable operation

Applications

• Drinking water disinfection monitoring
• Municipal water treatment plants
• Food and beverage processing
• Pharmaceutical water systems
• Cooling tower water treatment
• Hospital water systems
• Swimming pool and spa disinfection
• Wastewater treatment
• Industrial process water
• Odor control systems

Technical Specifications

The ClO2-100 delivers precise chlorine dioxide measurements from 0.01 to 20.00 mg/L with automatic temperature compensation via the integrated PT1000 sensor. The sensor technology specifically detects ClO2 molecules, providing accurate measurements without cross-sensitivity to free chlorine or other oxidants.

Understanding Chlorine Dioxide

Chlorine dioxide offers several advantages as a disinfectant:

• More Effective: Stronger oxidant than chlorine
• Safer Byproducts: Does not produce trihalomethanes (THMs) or haloacetic acids (HAAs)
• pH Independent: Effective across wide pH range (4-10)
• Biofilm Control: Superior penetration of biofilms
• Taste and Odor: Better control of taste and odor compounds

Typical ClO2 residuals:

• Drinking water: 0.1-0.8 mg/L
• Industrial applications: 0.5-5.0 mg/L
• Shock treatment: 5.0-20.0 mg/L

Connectivity and Integration

The ClO2-100 supports dual output for integration into disinfection control systems:

RS485 Modbus RTU:

• Connect to Agrinovo Omni Genesis or Exodus controllers for cloud-based ClO2 monitoring
• Multi-drop bus networking (up to 32 sensors per bus)
• Standard Modbus registers for ClO2 concentration and temperature
• Compatible with SCADA, PLC, and water treatment plant automation systems

RS485 Modbus RTU Output:

• Direct connection to ClO2 generator dosing controllers
• Feedback loop control for maintaining target residual levels
• Scalable output range mapped to measurement range

IoT Integration:

• Pair with Omni Genesis/Exodus for remote disinfection monitoring
• Set automated alerts for under-dosing or over-dosing conditions
• Historical data logging for regulatory compliance documentation
• Integrate with ClO2 generator controls for automated dosing

Installation and Maintenance

Positioning: Install downstream of the ClO2 injection point, after adequate contact time and mixing. For distribution systems, install at representative points in the network. Avoid locations with stagnant water or air pockets that could trap ClO2 gas.

Calibration: Two-point calibration using freshly prepared ClO2 standards. Calibrate at 0.2 mg/L and 2.0 mg/L for drinking water applications. ClO2 standards degrade quickly - prepare fresh before each calibration. Recalibrate every 1-2 weeks.

Membrane Care: Inspect the sensing membrane monthly. Clean with deionized water to remove deposits. Replace the membrane when response time exceeds specifications or when calibration stability degrades.

Safety Considerations

Chlorine dioxide monitoring is critical for maintaining safe and effective disinfection:

• Under-dosing: Inadequate pathogen inactivation, potential health risks
• Over-dosing: Chlorite byproduct formation (EPA MCL: 1.0 mg/L), taste and odor complaints
• Maximum Residual: EPA MRDL for ClO2 is 0.8 mg/L in drinking water
• Contact Time: Adequate CT values required for disinfection credit

Related Guide: ClO2 Monitoring in Water Treatment: Sensor Types, Methods & Compliance