Condumax CLS21

Summary

Product identification

Product Name: Condumax CLS21D/CLS21 Product Type: Conductivity sensors, analog or digital with Memosens technology

Application

Suitable for measurement in media with average or high conductivity, including:

• Separation of media with average conductivity (e.g., milk/water)
• Separation of media with high conductivity (e.g., alkali/water)
• Drinking water treatment
• Wastewater treatment

Sensors with temperature probes are intended for use with conductivity measuring devices that support automatic temperature compensation.

Measuring Principle

Utilizes conductive measurement of conductivity by applying an alternating voltage between two electrodes immersed in the medium. Conductivity (κ) is calculated based on Ohm's Law and the cell constant (k), which is dependent on sensor geometry.

Measuring System

A complete measuring system comprises:

• Conductivity sensor (CLS21D or CLS21)
• Transmitter (e.g., Liquiline M CM42)
• Measuring cable (e.g., Memosens data cable CYK10 or CYK71 for analog sensors)

Communication and Data Processing (CLS21D only)

Digital sensors with Memosens technology enable non-contact, inductive signal transmission. They can store sensor data including:

• Manufacturer data (serial number, order code, date of manufacture)
• Calibration data (date, cell constant, delta cell constant, number of calibrations, serial number of last used transmitter)
• Operating data (temperature and conductivity application ranges, commissioning date, maximum temperature, hours of operation at high temperatures)

Memosens technology digitizes measured values within the sensor, ensuring maximum process safety, data security, and simplified operation through automatic data transfer and sensor-independent calibration.

Input

• Measured values: Conductivity, Temperature
• Conductivity measuring ranges (in relation to water at 25 °C): 10 μS/cm to 20 mS/cm
• Temperature measuring ranges:
  • CLS21D: -20 to 100 °C (-4 to 212 °F)
  • CLS21: -20 to 135 °C (-4 to 275 °F)
• Cell constant: k = 1.0 cm⁻¹, nominal

Temperature Compensation

• NTC 30K (CLS21D)
• Pt100 (Class B as per IEC 60751) (CLS21)

Electrical Connection

• CLS21D: Utilizes measuring cable CYK10 for connection to a Memosens transmitter.
• CLS21: Connected via a fixed cable or CYK71 measuring cable. Wiring diagrams are provided in the transmitter's Operating Instructions.

Performance Characteristics (CLS21D)

• Response time (Conductivity): t<0xE2><0x82><0x95> ≤ 3 s
• Response time (Temperature): t<0xE2><0x82><0x90> ≤ 296 s
• Maximum measured error: 5% of reading
• Repeatability: 0.2% of reading

Installation

Sensors can be installed directly via the process connection or optionally using a flow assembly (CLA751, CLA752) or immersion assembly (Dipfit CLA111).

Environment

• Ambient temperature: -20 to +60 °C (-4 to 140 °F)
• Storage temperature: -25 to +80 °C (-10 to +180 °F)
• Humidity: 5 to 95 %
• Degree of protection:
  • CLS21D: IP 68 / NEMA type 6P
  • CLS21 (Fixed cable): IP 67 / NEMA 6
  • CLS21 (Plug-in head): IP 65 / NEMA 4X

Process Conditions

• Process temperature:
  • CLS21D: -20 to 135 °C (-4 to 275 °F) at 3.5 bar (50 psi) absolute
  • CLS21 (Threaded with fixed cable): -20 to 100 °C (-4 to 212 °F)
  • CLS21 (Plug-in head, Clamp): -20 to 135 °C (-4 to 275 °F) at 3.5 bar (50 psi) absolute
  • Maximum temperature for communication with Memosens transmitters: 130 °C (266°F)
• Process pressure (absolute): 17 bar (246 psi) absolute, at 20 °C (68 °F)

Mechanical Construction

• CLS21D: Features a Memosens plug-in head, process connection (e.g., G1), graphite electrodes, and wrench flats.
• CLS21: Available with a plug-in head (four-pin connector, cable gland Pg9, process connection e.g., DN 40 dairy pipe) or a fixed cable (process connection e.g., NPT 1" thread).

Dimensions

Detailed dimensions for CLS21D and CLS21 are provided in mm (inches) for various connection types (G1, Clamp 2", Sanitary, NPT 1").

Weight

Approximately 0.3 kg (0.66 lbs) depending on the version.

Materials (in contact with medium)

• Electrodes: Graphite
• Sensor shaft: Polyethersulfone (PES-GF20)
• Thermal conductivity socket: Titanium 3.7035
• Clamp process connection: Stainless steel 1.4435 (process connection), EPDM (seal)

Process Connections

• Thread G1
• NPT 1" thread
• Clamp 2" as per ISO 2852
• Sanitary connection DN 25 and DN 40 as per DIN 11851

Certificates and Approvals

• CE mark: Complies with EU directives.
• Ex approvals: Various ATEX, NEPSI, IECEx, and EAC Ex approvals are available depending on the model and intended zone. Memosens sensors for hazardous areas are indicated by colored rings on the plug-in head.
• Manufacturer inspection certificate: Provided, stating the individual cell constant.

Accessories

• Assemblies: Dipfit CLA111 (immersion assembly), Flow assembly CLA751, Flow assembly CLA752
• Measuring cable: CYK10 Memosens data cable, CYK11 Memosens extension cable, CYK71 (unterminated cable)
• Junction boxes (CLS21 only): VBM, VBM-Ex
• Calibration solutions: Conductivity calibration solutions CLY11 (various concentrations)

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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