Sensorex Expands Line of pH/ORP Sensors

Sensorex Expands SD7000 Differential pH/ORP Sensor Line


New sensors compatible with a wider range of process monitoring systems for water, wastewater, environmental scrubber and other challenging applications

Sensorex has expanded its SD7000 family of Differential pH/ORP Sensors, adding four new models to suit a wider range of online process monitoring applications. Sensorex’s proven differential sensor technology produces highly accurate measurements with an overall low cost of ownership. They are ideally suited for measuring pH and ORP in industrial and municipal wastewater treatment and neutralization; metal finishing and plating; wet fume scrubbers; chemical processing; and other online water quality and process applications.


The three electrode differential sensor design results in less maintenance for operators, minimized down time, longer sensor life and overall greater reliability. Process pH or ORP is measured differentially with process and protected inner reference electrodes, compared to a third ground electrode. The inner reference electrode is surrounded by a known concentrated pH 7 buffer that resists process contamination, maintaining its pH level with minimal dilution effects. A double junction salt bridge further guards against contamination. Both the standard pH 7 cell solution and salt bridge can be replaced periodically at a much lower cost than total sensor replacement.

The new SD7500CD and SD7500CD-ORP are universally compatible with any conventional pH/ORP transmitter or controller, including Sensorex products. The new SD7420CD and SD7420CD-ORP include a direct 4-20mA output for integration into process control systems without requiring an additional 4-20mA transmitter or controller. These sensors are also a direct replacement option for some Hach® and Water Analytics®/Aquametrix probes, as follows:


  • Hach 6428P0 (LCP body)
  • Hach 6422P0 (Ryton body)
  • Water Analytics P65C-8 pH (CPVC Body)


  • Hach 2428R0 (LCP body)
  • Hach 2422R0 (Ryton body)
  • Water Analytics R65C-8 (CPVC body)

About Sensorex
At Sensorex, we believe that even the most complex water analysis should be fast and simple to perform. We’ve introduced some ground-breaking technologies since our initial launch in 1972, and today, we remain focused on the continual advancement of water quality monitoring products. We promise a seamless buying experience with fast shipping, industry-leading warranty programs, and reliable water quality sensors and instrumentation.

To learn more about Sensorex visit

*Hach is a registered trademark of the Hach Company. Aquametrix is a product of Water Analytics Inc. No affiliation, endorsement or sponsorship is stated or implied.