It is designed to monitor free chlorine in drinking water, rinse water, cooling water or other fresh water samples from 0.05 – 20 PPM Cl2. The FCA22 features a plug and play design that incorporates a flow control device, a pH sensor, a chlorine sensor and the analyzer/ controller conveniently mounted on a PVC panel. Connect the sample and drain lines, connect the power and outputs and it is ready to use. Calibration is accomplished by DPD comparison.