Free Chlorine (FCL) Sensor

Free chlorine (FCL) refers to the available chlorine in water that remains active for disinfection—primarily in the form of hypochlorous acid (HOCl) and hypochlorite ions (OCl⁻). FCL sensors are essential in monitoring and controlling chlorine levels in drinking water, pools, industrial wastewater, and disinfection systems to ensure safe, effective treatment and regulatory compliance.

HH SCIENCE’s Free Chlorine Sensors utilize proven electrochemical measurement technology, such as amperometric methods, to detect chlorine concentration in real time. Our sensors feature high-purity platinum rings, robust reference systems, and stable output for continuous and accurate measurement—even under fluctuating temperature or flow conditions. Integrated with advanced signal processing and RS485 Modbus RTU communication, our FCL sensors are easy to install, integrate, and maintain across various applications.

Whether you’re operating a municipal water plant, a pool facility, or an industrial disinfection system, HH SCIENCE sensors offer unmatched precision, low drift, and long service life. Their strong anti-interference capability and dual junction reference design make them ideal for long-term use, minimizing maintenance needs.

Choose HH SCIENCE to ensure reliable free chlorine monitoring that helps you meet safety standards while reducing operational costs. We offer both standard and OEM/customizable models.