While the theory of monitoring conductivity is simple, in practice it can be very frustrating. While simple 2-electrode sensors are inexpensive and can provide accurate data, continuous water quality monitoring of even relatively clean water can foul the electrodes and degrade the measurement. Maintaining accuracy is made more difficult when the amount of solids dissolved in the process varies over a wide concentration range.
ATI’s Q46C4 4-Electrode Conductivity Water Quality Monitor is the answer for monitoring almost any water-based process. Drinking water, plating bath solutions, cooling water, process wash water, or virtually any other aqueous system can be monitored accurately and reliably. The unique drive/control scheme used in the 4-electrode system allows a single sensor to be used in conductivity ranged from 0-200 μS to as high as 0-2,000 mS (0-2S). For chemical mixing applications, a concentration display can be selected.
Sensors for the Q46C4 system are available in a variety of mounting configurations: convertible-style with 1” NPT threads for pipe or tank mounting, 1-1/2” or 2” sanitary-style fittings in 316 stainless steel, and insertion-style for 1-1/4” NPT hot-tap assemblies that allow the sensor to be removed from service without shutting down the process. For low flow bypass applications, a Noryl sensor with quick-disconnect cable and acrylic flowcell are available.