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Digital conductivity sensor
Condumax CLS21D

Digital conductivity sensor
Condumax CLS21D ©Endress+Hauser

The conductivity of a liquid can be measured using the conductive or toroidal measuring principles. This video shows what it is about and how these measuring principles work.

Memosens converts the measured value to a digital signal and transfers it to the transmitter without a contacting connection. This video shows how Memosens optimizes process control and maintenance.

Memosens conductive conductivity sensor for medium to high measuring ranges

Condumax CLS21D is a robust conductivity sensor for all process and environmental applications. It provides you with precise and reliable measuring values for an optimum process and product quality monitoring. Better still, the sensor features high chemical, thermal and mechanical stability and high durability. Thanks to Memosens digital technology, CLS21D combines maximum process and data integrity with simple operation. It resists corrosion and moisture and facilitates predictive maintenance.

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  • Benefits

    • Reliable and accurate measuring values at medium to high conductivities

    • Robust design for long durability and low maintenance

    • High chemical, thermal and mechanical stability

    • Quality certificate stating the individual cell constant

    • Logging of sensor-...

  • Field of application

    Condumax CLS21D measures conductivity in all process and environmental applications, such as:

    • Potable water treatment

    • Desalination plants

    • Industrial water treatment

    • River/lake monitoring

    • Phase separation in medium conductivities (e.g. milk/water)


Features and specifications



  • Measuring principle


  • Application

    Water, waste water, process, media separation, industrial water

  • Characteristic

    2-electrode system for application in the middle application range

  • Measurement range

    k=1: 10 µS/cm to 20 mS/cm

  • Measuring principle

    Conductive conductivity cell with graphite electrodes for applications in the middle range

  • Design

    2-electrode system with parallel arranged electrodes

  • Material

    Sensor shaft: PES
    Electrodes: graphite

  • Dimension

    Diameter: 24 mm (0.94 inch)
    Length: 61 mm (2.40 inch)

  • Process temperature

    -20 to 135 °C at 3.5 bar abs
    (-4 to 275 °F at 50 psi)

  • Process pressure

    17 bar abs at 20 °C
    (246 psi at 68 °F)

  • Temperature sensor

    NTC 30K

  • Ex certification


  • Connection

    Process connection: DN25, DN40, G1, NPT 1"
    Cable: Memosens connector CYK10

  • Ingres protection

    IP68 (connector)

Documents / Manuals / Software

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