Model 389 pH/ORP Sensors

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NEW QUICK CABLE-TO-SENSOR RELEASE, provided by the watertight VP multiple-pin connector, eliminates cable twisting. LONGER SENSOR LIFE provided by triple junction reference cell in process solutions containing poisoning ions. OPTIMUM VERSITILITY for various mounting options provided by one-piece construction with process threads in two places. MAXIMUM CHEMICAL RESISTANCE provided by rugged Tefzel®¹ body, completely sealed to eliminate sensor leakage. NOISE FREE, LONG DISTANCE TRANSMISSION of the high impedance pH signal provided by integral preamplifier. ENHANCED PERFORMANCE AND INCREASED LIFE with minimized glass cracking provided by field-proven AccuGlass® pH glass formulations.

FEATURES AND APPLICATIONS The reference junction aids in the sensor’s resistance to poisoning ions and helps prolong sensor life. Models 389 and 389VP are provided with a triple junction reference, which protects the reference element from poisoning ions such as ammonia, chlorine, cyanides, and sulfides in the process. Both models are made with an outer ceramic junction constructed in an annular design around the pH/ORP-sensitive membrane. The AccuGlass® pH glass formulations exceed industry standards. The AccuGlass® pH glass is a result of many years of glass research resulting in a formulation which has been found to increase the life of the sensor. Unlike other pH glasses presently on the market, this glass resists cracking especially at higher temperatures and reduces sodium ion error commonly found in high pH applications. Overall, the AccuGlass® formulation enhances the sensor performance to measure pH more accurately and have a longer sensor life than ever before. A choice of pH glass electrodes is available to best meet various application needs. Two types are available: hemi bulb and high pH glass. The AccuGlass® hemi bulb is the standard glass offered on both models and can be used for most applications. The hemi bulb is also found on the high pH glass option. NEW - Model 389VP is offered with a watertight sensor-to-cable connector which eliminates re-wiring and cable twisting when replacing sensors. The Variopol VP multiple pin connector is an integral part of each sensor model and uses a mating VP cable. Once the cable is installed and wired to the analyzer, sensors are easily replaced without replacing the cable and without rewiring the analyzer. Also the cable can be disconnected from the sensor before removal from the process which eliminates cable twisting. Models 389 and 389VP are housed in a molded Tefzel® body with Viton® o-rings, making each sensor virtually indestructible and chemically resistant. Complete encapsulation eliminates leakage or high humidity problems traditionally found in other pH/ORP designs. The simplified construction, designed with user convenience in mind does not require electrolyte (KCl) replenishment or any high maintenance troubleshooting procedures. A preamplifier converts the high impedance pH signal into a stable, noise-free signal and must be used with all pH sensors. The Model 389 offers the choice of an integral sensor preamplifier. Both Models can use a remote preamplifier, integral to the analyzer/transmitter or in a remote junction box. All preamplifiers have a transmission capability of up to three miles.The Rosemount Analytical preamplifier method has become the industry standard for pH/ORP measurement reliability. Installation is easily achieved through the wide variety of mounting configurations. Both Models feature 1 inch (MNPT) front and rear facing connections for insertion, submersion, or flow-through pH and ORP applications. Both models are combination sensors (pH, reference, and temperature within sensor body) and measure pH or ORP (Oxidation/Reduction Potential) of aqueous solutions in pipelines, open tanks, or ponds. Models 389 and 389VP are suitable for virtually all applications and are compatible with Rosemount Analytical and other manufacturers’ instruments. Viton® is a registered trademark DuPont Performance Elastomers. Kalrez® is a registered trademark DuPont Performance Elastomers. Tefzel® is a registered trademark DuPont Films. AccuGlass® is a registered trademark of Rosemount Analytical, Inc. TUpH® is a registered trademark of Rosemount Analytical, Inc.