ATi (Analytical Technology, Inc.) Q45C4 4-Electrode Conductivity Monitor Conductivity and Resistivity Meter

While simple two-electrode sensors are inexpensive and can provide accurate data,continuous monitoring of even relatively clean water can contaminate the electrodes and reduce measurement accuracy. Main accuracy becomes more difficult when the amount of solids dissolved in the process varies over a wide range of concentrations. In this case,a simple two-electrode sensor is limited by its cell constant,which means it cannot accurately measure the process.,ATI’s Q45C4 4-electrode conductivity monitor is the answer to monitoring virtually any water-based process. Drinking water,plating baths,cooling water,process rinse water or virtually any other water system can be monitored accurately and reliably. The unique drive/control scheme used in the 4-electrode system allows the use of a single sensor configuration over conductivity ranges from 0-200 μS up to 0-2000 mS (0-2 S). The CAUTO ranging function enables the monitor to display actual conductivity values under coverage shooting conditions. For chemical applications,concentration displays are available for a limited number of acids and bases. In a traditional two-electrode sensor,each electrode performs two functions. First,electrodes are used to generate a driving potential through an aqueous solution. Second,electrodes are used to measure the level of electrical current as the conductivity of the solution changes. It is this dual effect that limits two-electrode sensors to a narrow functional conduction range.,a four-electrode sensor separates the two functions between two sets of electrodes. A set of electrodes is used to generate a driving potential through an aqueous solution. Another set of electrodes is used to measure the current between the two drive electrodes. Since these two functions are separate,4-electrode sensors are not affected by polarization effects,limiting 2-electrode sensors to a narrow functional range. This enables a 4-electrode sensor to operate reliably over the entire 0-2 S\/cm conductivity range.