Memosens CLS15E

Summary

Product identification

• Product Name: Memosens CLS15E
• Product Type: Digital conductivity sensor with Memosens 2.0 technology
• Document ID: TI01526C/07/EN/01.20
• Date: 2021-01-31

Application

Measurements in pure and ultrapure water. Typical applications include:

• Monitoring of ion exchangers
• Reverse osmosis
• Distillation
• Chip cleaning

This sensor is used in conjunction with conductivity measuring devices that support automatic temperature compensation, such as:

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

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

Measuring principle

Conductivity is determined by applying an alternating voltage across two electrodes immersed in the medium. The resulting current flow is measured, and based on Ohm's law, the electrical resistance and conductance are calculated. The specific conductance (κ) is derived using the cell constant (k), which is dependent on the sensor geometry.

Measuring system

A complete measuring system comprises:

• Conductivity sensor Memosens CLS15E
• Transmitter (e.g., Liquiline M CM42)
• Measuring cable (e.g., Memosens data cable CYK10)

Communication and data processing

Digital sensors with Memosens technology must be connected to a transmitter with Memosens technology. Data transmission to transmitters designed for analog sensors is not possible.

Digital sensors can store various 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 the transmitter used for the last calibration
• Operating data (temperature and conductivity application ranges, date of initial commissioning, maximum temperature, hours of operation at high temperatures)

Dependability

Reliability

Memosens technology digitizes measured values within the sensor and transmits them digitally to the transmitter. This system reliably detects and reports sensor failures, connection interruptions, and the availability of the measuring point.

Maintainability

Sensors with Memosens technology feature integrated electronics that store calibration data and operational history. This allows for:

• Independent calibration and adjustment in a lab environment.
• Quick replacement of pre-calibrated sensors, increasing measuring point availability.
• Accurate definition of maintenance intervals and predictive maintenance based on sensor load data.
• Documentation of sensor history for application optimization.

Integrity

The inductive, non-contact data transmission of Memosens technology ensures process safety by eliminating issues related to moisture, corrosion at the connection, and measured value distortion. The plug-in system can be connected underwater, and the transmitter is galvanically decoupled from the medium. EMC safety is ensured through screening measures for digital transmission.

Input

Measured variables

• Conductivity
• Temperature

Measuring ranges

• Conductivity:
  • CLS15E-******A: 40 nS/cm to 20 µS/cm
  • CLS15E-******B: 100 nS/cm to 200 µS/cm (Values are in relation to water at 25 °C (77 °F))
• Temperature: -20 to 140 °C (-4 to 284 °F)

Cell constant

• CLS15E-******A: k = 0.01 cm⁻¹
• CLS15E-******B: k = 0.1 cm⁻¹

Temperature compensation

• Pt1000 (Class A according to IEC 60751)

Power supply / Electrical connection

• Requires a measuring cable CYK10 for connection to the transmitter.

Performance characteristics

Uncertainty of measurement

• Uncertainty in determining the cell constant is 1.0 %. Each sensor is factory-measured using a NIST or PTB traceable reference system. The exact cell constant is provided on the manufacturer inspection certificate.

Response time

• Conductivity: t₉₅ ≤ 2 s
• Temperature:
  • CLS15E-******A: t₉₀ ≤ 16 s (with temperature prediction activated)
  • CLS15E-******B: t₉₀ ≤ 8 s (with temperature prediction activated) (Based on DIN VDI/VDE 3522-2, 0.3 m/s laminar flow)

Measured error

• Conductivity: ≤ 2 % of reading, within the specified measuring range.
• Temperature:
  • ≤ 0.5 K, from -5 to 100 °C (23 to 212 °F).
  • ≤ 1.0 K, from 100 to 140 °C (212 to 284 °F).

Repeatability

• Conductivity: ≤ 0.2 % of reading, within the specified measuring range.
• Temperature: ≤ 0.05 K.

Installation

Installation instructions

Sensors can be installed directly via the process connection (e.g., Clamp) or optionally using a T-piece, cross fitting, or a flow 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 (submersion in water at 1 m water column, 25 °C, 24 h)

Process

Process temperature

• Normal operation: -20 to 120 °C (-4 to 248 °F)
• Sterilization (max. 1 h): Max. 140 °C (284 °F) (Threaded versions: max. 30 minutes for sterilization)

Process pressure

• 13 bar (188 psi) absolute, at 20 °C (68 °F)
• 2 bar (29 psi) absolute, at 120 °C (248 °F)

Mechanical construction

Design

• Features a Memosens plug-in head, wrench flats for mounting, minimum immersion depth, coaxial measuring electrodes, and a process connection (thread or clamp).

Dimensions

• See diagrams on pages 8 and 9 for specific dimensions in mm (in) for thread and clamp versions.

Weight

• Approx. 0.3 kg (0.66 lbs) depending on the version.

Materials (in contact with medium)

• Electrodes: Polished, stainless steel 1.4435 (AISI 316L)
• Sensor shaft: Polyethersulfone (PES-GF20)
• O-ring (Clamp version only): EPDM

Materials (not in contact with medium)

• An internal connector contains lead (CAS number 7439-92-1) at over 0.1 % (w/w), as per REACH Regulation (EC) 1907/2006. The product is not hazardous when used as intended.

Process connection

• Thread: NPT ½" and ¾"
• Clamp: 1½" as per ISO 2852

Surface roughness

• Ra ≤ 0.8 μm

Certificates and approvals

Certificates and approvals are optional and depend on the product version.

• CE mark: Confirms compliance with EU directives.
• Hazardous area approvals: Various certifications including ATEX (Ex ia IIC T3/T4/T6 Ga), CSA C/US, and EAC Ex are available for specific model variants.
• Test reports: Manufacturer inspection certificate stating the individual cell constant.
• Additional certification: Inspection certificate in accordance with EN 10204 3.1 is available depending on the version.
• Other standards and guidelines: EAC conformity mark indicates compliance with TP TC 004/2011 and TP TC 020/2011.

Ordering information

Detailed ordering information, product configuration, and scope of delivery can be found on the product page: www.endress.com/cls15e.

Accessories

• Threaded and adapter couplings: Available in PVC and PVDF for various fitting sizes.
• Flow assembly: Stainless steel assembly for sensors with NPT ½" thread.
• Measuring cable: Memosens data cables CYK10 and CYK11.
• Calibration solutions: CLY11 precision solutions referenced to NIST SRM.
• Calibration set: Conducal CLY421 for ultrapure water applications.

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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