The Model 410VP four-electrode conductivity sensor is intended primarily for the determination of electrolytic conductivity in the pharmaceutical and food and beverage industries. Typical applications include monitoring the concentration of CIP solutions and rinses, monitoring eluents in chromatographic separations, and detecting liquid interfaces.

FEATURES
The Model 410VP sensor has a flat sensing face consisting of four circular electrodes arranged in a row. The analyzer injects an alternating current through the outer electrodes and measures the voltage across the inner electrodes. The conductance of the electrolyte solution between the voltage electrodes is readily calculated from the measured current and voltage. Because the voltage measuring circuit draws almost no current, errors caused by series capacitance and cable resistance, which are significant in two-electrode measurements at high conductivity, are greatly reduced. The Model 410VP sensor covers the range 1 uS/cm to 1400 mS/cm.

Electrolytic conductivity is a strong function of temperature, and conductivity readings are typically corrected to a reference temperature. The Model 410VP senses temperature using a Pt1000 RTD. The RTD contacts the process liquid through a stainless steel face, so response to temperature changes is rapid.

The Model 410VP sensor is available in four sanitary connections: 1½ inch and 2-inch Tri-Clamp, Varivent N, and G 1¼. All wetted plastics and elastomers (G 1¼ version only) are compliant with 21CFR177, and all wetted surfaces except the electrodes have a 16 microinch (0.4 micrometer) Ra finish. The sensor is shipped with a certificate of conformance for materials and surface finish. A supplier material traceability certificate is also available as an option.

1 Tri-Clamp is a registered trademark of Alfa Laval, Inc.
2 Varivent is a registered trademark of Tuchenhagen, GmbH.