Designed & made in India · Since 2018 Customer support Become a partner UONO Cloud login
New: UONO Universal Industrial IoT Gateway, launching at Bengaluru Tech Summit 2026 · 17 Nov · BIEC Hall 4Discover UONO
← Back to Sensors

Chlorine Sensor (Free & Total Chlorine)

Measuring disinfectant levels to ensure safety, hygiene, and regulatory compliance.

What Does a Chlorine Sensor Measure?

A chlorine sensor measures the concentration of chlorine present in water or process fluids, typically expressed in mg/L or ppm. Measurements may represent free chlorine, combined chlorine, or total chlorine depending on the application. Chlorine monitoring is critical for disinfection effectiveness and prevention of over-dosing.

Working Principle

Chlorine sensors operate by detecting chlorine through electrochemical or optical reactions. The sensing element selectively responds to chlorine species, producing a signal proportional to concentration.

  • Amperometric electrochemical detection
  • Membrane-covered sensing electrodes
  • Colorimetric and optical detection methods

Common Types of Chlorine Sensors

  • Free Chlorine Sensors
  • Total Chlorine Sensors
  • Inline Chlorine Probes
  • Chlorine Analyzers with Transmitters
  • Portable Chlorine Measurement Devices

Signals & Outputs

  • Analog: 4–20 mA
  • Digital: RS-485 (Modbus RTU)
  • Industrial Ethernet (via analyzers)
  • Measured in mg/L (ppm) as Free Chlorine, Total Chlorine, or Combined Chlorine

Sensor Cluster

This sensor belongs to the Process Quality Cluster, focusing on disinfection control, pathogen inactivation, chemical dosing accuracy, and regulatory compliance.

Direct & Indirect Meaning of Chlorine Data

Direct Meaning

The measured value directly represents the concentration of chlorine in a liquid.

Indirect Meaning

Chlorine trends indirectly indicate disinfection effectiveness, pathogen control reliability, chemical dosing efficiency, and risks of corrosion or harmful by-product formation.

Industries Using Chlorine Sensors

Role of IoT in Chlorine Monitoring

With Industrial IoT integration, chlorine sensors enable continuous disinfection monitoring, automated dosing control, real-time safety alerts, and compliance-ready water quality reporting.

IndustrioPedia Perspective

The Chlorine Sensor is the final gatekeeper of public health. By ensuring effective yet controlled disinfection, it protects consumers, safeguards infrastructure, and upholds trust in water and process systems.