Chlorine Sensors

Chlorine residual is the parameter that proves water is safe: too little and disinfection is incomplete, too much and taste, corrosion and regulatory limits become the problem. An online chlorine sensor gives the continuous measurement that grab samples and colorimetric tests cannot, and lets the dosing pump be controlled automatically.

The sensors are amperometric membrane cells that consume no reagents. Three versions cover free chlorine (hypochlorous acid and hypochlorite), total chlorine and monochloramine, each over 0 to 6 ppm with a 1" MNPT connection for the low-flow cell that keeps sample velocity constant across the membrane. Process conditions are 0 to 50 °C and up to 4.5 bar. Because free chlorine speciation depends on pH, the free chlorine version is normally paired with a pH sensor in the same flow cell so the transmitter can compensate automatically.

The transmitter delivers 4–20 mA, HART or FOUNDATION Fieldbus and drives the dosing control loop; flow cells, panels, rotameters and calibration solutions come from the accessories range.

Applications are drinking water disinfection, distribution network monitoring, wastewater effluent disinfection, cooling and process water treatment, and low-flow chlorine monitoring in municipal water, industrial water treatment, wastewater treatment and utilities.