Reliable Conductivity Measurement for Water Applications

The CLS21E is designed for applications with medium conductivity levels, providing stable and accurate conductivity measurement for various water treatment and industrial processes.

Its robust mechanical construction and corrosion-resistant design support long-term operation in demanding environments.

Designed for Medium Conductivity Applications

Unlike CLS15E, which focuses on low conductivity pure water applications, CLS21E is optimized for general water quality monitoring where conductivity values are higher.

Typical applications include:

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  Drinking water treatment
  
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  Desalination plants
  
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  Industrial water treatment
  
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  Surface water monitoring
  
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  Process water systems
  

Memosens 2.0 Digital Technology

With Memosens 2.0, the CLS21E stores important sensor information including calibration data directly in the sensor.

This improves measurement reliability, simplifies maintenance and supports predictive maintenance strategies.

Robust Two-Electrode Design

The CLS21E uses a conductive measurement principle with parallel graphite electrodes.

This design provides reliable conductivity measurement while maintaining good mechanical stability for industrial applications.

Key Features

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  Digital conductivity sensor
  
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  Memosens 2.0 technology
  
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  Two-electrode conductive measurement principle
  
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  Graphite electrode design
  
• 
  Designed for medium conductivity applications
  
• 
  Measuring range: 10 μS/cm to 20 mS/cm
  
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  Integrated Pt1000 temperature sensor
  
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  Sensor material: PES shaft with graphite electrodes
  
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  Process temperature: -20 to 135°C
  
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  Process pressure: up to 17 bar abs at 20°C
  
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  Diameter: 24 mm
  
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  IP68 protection
  
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  Hazardous area approvals available
  
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  Suitable for drinking water, industrial water and surface water applications
  

Typical Applications

Drinking Water Treatment

Used for conductivity monitoring in drinking water production and distribution systems.

Desalination Plants

Suitable for monitoring water quality during desalination processes.

Industrial Water Treatment

Used in industrial water systems where reliable conductivity measurement is required.

Surface Water Monitoring

Suitable for monitoring conductivity changes in rivers, lakes and other surface water sources.

FAQ

What is the Endress+Hauser CLS21E?

The CLS21E is a digital conductivity sensor designed for medium conductivity water applications using Memosens 2.0 technology.

What is the difference between CLS15E and CLS21E?

CLS15E is mainly designed for low conductivity pure and ultrapure water applications, while CLS21E is designed for medium conductivity water monitoring, such as drinking water and industrial water systems.

What does CLS21E measure?

The CLS21E measures the electrical conductivity of liquids using a two-electrode conductive measuring principle.

What is the measuring range of CLS21E?

The measuring range is:

10 μS/cm to 20 mS/cm (cell constant k=1).

Does CLS21E support Memosens 2.0?

Yes. The CLS21E uses Memosens 2.0 digital technology for secure sensor data management and easier maintenance.