Electro-Chemical Devices” TCA-22 Analyzer System features built-in pH compensation in a virtual plumb-and-play design. The total chlorine analyzer is designed for use in drinking water, industrial cooling and rinse water, wastewater or other fresh water samples containing chlorine in the range of 0-20 PPM. It is a good fit for applications in municipal water systems and a range of water-based processes in the chemical, electronics, electric power, food/beverage, oil/gas, pharmaceutical, pulp/paper and other industries. The unit’s total chlorine amperometric sensor features a built-in pH sensor that automatically compensates for samples with a four to 12 pH concentration. This capability eliminates the need for sample conditioning systems with consumable reagents to control the pH level in the solution. The amperometric sensor is a three-electrode design, which measures all chlorine species in the water, combined chlorine and free chlorine. The sensor is constructed with one gold cathode, one silver halide anode and a 304 stainless steel counter electrode. The counter electrode provides a stable base potential that minimizes drift for high accuracy. The sensor’s micro-porous membrane allows ions to diffuse in and out of the sensor. The various chlorine species in the measured sample diffuse into the sensor and react with the acidic potassium iodide electrolyte to form iodine. The iodine is reduced at the cathode back to iodide and the current flow between the cathode and silver iodide anode is proportional to total chlorine. While amperometric chlorine sensors are flow sensitive, the TCA-22 features a constant head flow control device (ECD) design. It maintains the optimum flow by the sensor over a range of incoming sample flowrates from 38 to 300 L/hr (10 to 80 gal/hr). It operates over a wide temperature range from 0 C to 45 C (32 F to 113 F). A built-in analyzer allows either total chlorine or pH to be displayed graphically. User-defined ranges allow easy trend analysis of either parameter. The panel-mount design of the sensor comes pre-wired and with assembled flow tubing. Advanced sensor and controller technologies allow installation and commissioning to be completed in just three steps. All that is necessary is to connect the sample and drain lines, connect the power and outputs. Calibration is accomplished by DPD comparison.