Memosens CLS21E

Summary

Product identification

Memosens CLS21E Digital conductivity sensor with Memosens technology.

Application

Designed for measurements in media with medium or high conductivity. Typical applications include:

• Separation of media with high conductivity (alkali/water)
• Drinking water treatment
• Wastewater treatment
• Cleaning of ballast water on ships
• Cleaning of water in a ship's wake

This sensor is used with transmitters that support automatic temperature compensation, such as:

• Liquiline CM442/CM444/CM448
• Liquiline CM42
• Liquiline CM14

Resistivity in MΩ · cm can also be measured with these transmitters.

Features

• Manufacturer inspection certificate stating the individual cell constant.
• Various designs for process or mounting adaptation.
• Suitable for installation in pipe or flow assembly.
• Compact design.
• High chemical, thermal, and mechanical resistance.
• Memosens technology provides maximum process safety, data security via digital transmission, easy usage with stored sensor data, and enables predictive maintenance.

Input

• Measured variables: Conductivity, Temperature
• Measuring ranges:
  • Conductivity: 10 μS/cm to 20 mS/cm (in relation to water at 25 °C)
  • Temperature: -20 to 135 °C (-4 to 275 °F)
• Cell constant: k = 1.0 cm⁻¹, nominal
• Temperature compensation: Pt1000 (Class A according to IEC 60751)

Performance characteristics

• Uncertainty of measurement (cell constant): 1.0 %
• Response time:
  • Conductivity: t<0xE2><0x82><0x95> ≤ 2 s
  • Temperature: t<0xE2><0x82><0x90> ≤ 30 s (with temperature prediction activated)
• Measured error:
  • Conductivity: ≤ 5 % of reading
  • Temperature: ≤ 2.5 K (for -20 to 100 °C); ≤ 3.5 K (for 100 to 135 °C)
• Repeatability:
  • Conductivity: ≤ 0.2 % of reading
  • Temperature: ≤ 0.05 K

Installation

Sensors are installed directly via the process connection or optionally via a flow or immersion assembly.

Environment

• Ambient temperature: -20 to 60 °C (-4 to 140 °F)
• Storage temperature: -25 to +80 °C (-10 to +180 °F)
• Degree of protection: IP 68 / NEMA type 6P

Process

• Process temperature: -20 to 135 °C (-4 to 275 °F) at 3.5 bar (50 psi) absolute
• Process pressure: 17 bar (247 psi) absolute at 20 °C (68 °F)

Mechanical construction

• Design: Includes Memosens plug-in head, process connection (G1 or NPT 1"), graphite coaxial measuring electrodes, and wrench flats.
• Dimensions: Refer to diagrams for specific dimensions in mm (in) for G1 and NPT 1" versions.
• Weight: Approx. 0.3 kg (0.66 lbs) depending on version.
• Materials (in contact with medium):
  • Electrodes: Graphite
  • Sensor shaft: Polyethersulfone (PES-GF20)
  • Thermal conductivity socket for temperature probe: Titanium 3.7035
• Materials (not in contact with medium): Contains lead (CAS 7439-92-1) in an internal connector (>0.1% w/w), but does not present a hazard if used as designated.
• Process connection: G1 thread or NPT 1" thread.

Certificates and approvals

Certificates and approvals are optional and depend on the product version. Available approvals may include:

• CE mark
• Hazardous area approvals (e.g., II 1 G Ex ia IIC T3/T4/T6 Ga, CSA C/US IS Cl. I Div. 1 GP A-D, AEx ia IIC T3/T4/T6, EAC Ex, NEPSI Ex)
• Marine approvals (ABS, BV, DNV-GL, LR)
• Manufacturer inspection certificate (stating individual cell constant)
• Inspection certificate in accordance with EN 10204 3.1 (depending on version)
• EAC certification

Ordering information

• Product details and configuration are available via the Product Configurator on the Endress+Hauser website.
• Scope of delivery: Sensor (as ordered), Operating Instructions.
• Accessories: Assemblies (Dipfit CLA111, Flow assembly CLA751, Flow assembly CLA752), Measuring cables (Memosens data cable CYK10, CYK11), Calibration solutions (CLY11 series).

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Disclaimer: This extraction may miss figures, footnotes, or revisions; contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

Lenntech datasheet mirror