Endress+Hauser CPS11D Series Conductivity Sensors

Technical Dossier

Product Details And Specifications

Endress+Hauser CPS11D Series: Comprehensive Module Range and Technical Overview

The Endress+Hauser CPS11D series represents a standardized product line of inductive and conductive conductivity sensors deployed across global heavy industry, including chemical processing plants, nuclear facility cooling circuits, oil refineries, pharmaceutical production, and water treatment infrastructure. The CPS11D platform is engineered for continuous inline measurement of liquid conductivity, concentration, and resistivity in aggressive media environments. Its hygienic and industrial variants are installed in tens of thousands of process loops worldwide, making it one of the most referenced sensor families in the Endress+Hauser Memosens ecosystem. The series supports both analog (4–20 mA) and digital (Memosens, HART, PROFIBUS PA, FOUNDATION Fieldbus) signal transmission, enabling integration into legacy DCS architectures as well as modern IIoT-ready control systems.

The Evolution of CPS11D Architecture

The CPS11D lineage originates from Endress+Hauser's earlier CPS1x and CPS4x conductive sensor families, which used conventional analog signal transmission with direct cable connections to transmitters such as the Mycom CLM153 and CLM223. These early-generation sensors required frequent recalibration due to analog signal drift over long cable runs and were susceptible to EMI in high-voltage industrial environments.

The CPS11D generation introduced the Memosens digital protocol as a core architecture shift. Memosens encodes the raw sensor signal digitally at the sensor head, transmitting it inductively via a standard M12 connector. This eliminates galvanic contact corrosion, enables hot-plug calibration in the laboratory, and stores calibration history, sensor identity, and process data directly in the sensor head's EEPROM. The CPS11D is therefore fully compatible with the Liquiline CM44x, Mycom CLM152, and Liquiline M CM42 transmitter families.

As of 2024, the CPS11D series has entered the mature/sustained phase of its product lifecycle. Endress+Hauser continues to manufacture and supply the full range, but successor platforms such as the CPS16D (with extended chemical resistance) and CPS41D (hygienic Tri-Clamp design) address application-specific requirements that the CPS11D does not cover. For installations requiring long-term maintenance support beyond standard product availability windows, DriveKNMS maintains a dedicated inventory of CPS11D variants to support lifecycle extension programs.

CPS11D Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly deployed configurations within the CPS11D product matrix. Each model code encodes electrode material, process connection, cable length, and output type per the Endress+Hauser ordering structure.

CPS11D-7BA21: Conductive conductivity sensor, PG 13.5 process connection, 120 mm insertion length, Memosens digital output, PVDF shaft, suitable for general industrial liquids up to 130°C / 6 bar.
CPS11D-7BA11: Conductive sensor, PG 13.5, 120 mm, analog 4–20 mA output, graphite electrodes, standard industrial process media.
CPS11D-7BA31: Conductive sensor, PG 13.5, 120 mm, Memosens output, titanium electrodes, enhanced chemical resistance for oxidizing media.
CPS11D-7BB21: Conductive sensor, PG 13.5, 225 mm insertion length, Memosens output, PVDF shaft, for deeper immersion process vessels.
CPS11D-7BB11: Conductive sensor, PG 13.5, 225 mm, analog output, graphite electrodes, standard process liquids.
CPS11D-7CA21: Conductive sensor, G 1/2 thread process connection, 120 mm, Memosens output, PVDF shaft, metric thread installations.
CPS11D-7CA11: Conductive sensor, G 1/2 thread, 120 mm, analog output, graphite electrodes, metric thread process connections.
CPS11D-7CB21: Conductive sensor, G 1/2 thread, 225 mm, Memosens output, PVDF shaft, deeper immersion metric installations.
CPS11D-7DA21: Conductive sensor, 1/2 NPT thread process connection, 120 mm, Memosens output, PVDF shaft, North American pipe standard installations.
CPS11D-7DA11: Conductive sensor, 1/2 NPT, 120 mm, analog output, graphite electrodes, NPT process connections.
CPS11D-7DB21: Conductive sensor, 1/2 NPT, 225 mm, Memosens output, PVDF shaft, extended insertion NPT installations.
CPS11D-7EA21: Conductive sensor, Varivent N DN25 hygienic connection, 120 mm, Memosens output, PVDF shaft, food and beverage CIP-compatible installations.
CPS11D-7EA11: Conductive sensor, Varivent N DN25, 120 mm, analog output, graphite electrodes, hygienic process connections.
CPS11D-7FA21: Conductive sensor, Tri-Clamp 1.5" hygienic connection, 120 mm, Memosens output, PVDF shaft, pharmaceutical and biotech CIP/SIP processes.
CPS11D-7FA11: Conductive sensor, Tri-Clamp 1.5", 120 mm, analog output, graphite electrodes, sanitary process connections.
CPS11D-7GA21: Conductive sensor, Ingold M12 hygienic connection, 120 mm, Memosens output, PVDF shaft, high-purity water and ultrapure process loops.

Sourcing Hard-to-Find & Obsolete CPS11D Parts

DriveKNMS maintains a dedicated stock program for the CPS11D series, with particular focus on analog-output variants (suffix -7BA11, -7CA11, -7DA11) that have been progressively phased out in favor of Memosens equivalents. These analog models remain in active service in installations using legacy Mycom CLM153, CLM223, and Liquisys CLM431 transmitters that do not support the Memosens protocol without a hardware upgrade.

For end-users operating CPS11D sensors in critical process loops — particularly in chemical dosing, cooling water treatment, and effluent monitoring — DriveKNMS provides the following lifecycle support services: verified surplus stock with full traceability documentation, functional testing against original Endress+Hauser factory specifications, cross-reference matching to identify compatible replacement models where direct equivalents are unavailable, and emergency dispatch for unplanned process shutdowns. All units are stored in climate-controlled conditions and shipped with calibration certificates upon request.

Quality Control for the CPS11D Range

Each CPS11D unit processed through DriveKNMS undergoes a structured inspection and functional verification protocol prior to dispatch. The procedure addresses the specific failure modes documented for this sensor family:

Electrode integrity check: Visual and dimensional inspection of graphite or titanium electrode rings for erosion, chemical attack, or mechanical damage. Electrode gap is verified against the factory specification of 1.0 mm ± 0.05 mm.
Shaft and seal inspection: PVDF shaft examined for stress cracking, chemical swelling, or deformation. O-ring seats inspected for compression set and chemical degradation. Replacement seals are sourced from Endress+Hauser-compatible materials (FKM, EPDM, FFKM).
Memosens connector verification: M12 inductive connector tested for signal integrity using a Memosens-compatible test adapter. EEPROM read/write function confirmed. Sensor identity data (serial number, calibration date, cell constant) verified as readable.
Cell constant verification: Sensor immersed in NIST-traceable KCl reference solution. Measured conductivity compared against certified reference value. Cell constant deviation must be within ±1% of the nominal value stamped on the sensor label.
Pressure and leak test: Process connection threads and shaft seals pressure-tested to 1.5× the rated process pressure (maximum 9 bar for standard variants) using inert gas.
High-voltage isolation test: Electrode circuit isolated from ground at 500 V DC for 60 seconds. Insulation resistance must exceed 100 MΩ.