These membrane-covered amperometric sensors are used to measure the concentration of free chlorine (e.g. drinking water, bath water, industrial water, process water, and cooling water). The sensor for free chlorine can be used to measure the following anorganic chlorination agents: chlorine gas (Cl2), electrolytically generated chlorine, sodium hypochlorite (NaOCl, chlorine bleaching solution), calcium hypochlorite (Ca(OCl)2), or chlorinated lime (Ca(OCl)Cl).
The sensors are not suitable for detecting the absence of free chlorine. The integrated electronics of the sensors provide a temperature-compensated current signal of 4 to 20 mA. Calibration is carried out in a downstream device (indicator, controller, recorder, PLC, etc.). The sensors can be connected directly to a suitable display and control device.