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Digital pH sensor Memosens CPS31E

Memosens 2.0 glass electrode for application in drinking water and swimming pools

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Digital pH sensor Memosens CPS31E

Memosens 2.0 glass electrode for application in drinking water and swimming pools

Get a quote
Office situation support
Have questions about this product?

Benefits

  • Reliable: Ceramic junction ensures reliable measurement at low conductivities. For minimum conductivities, 3 junctions are the best choice.
  • Robust: The optional salt storage provides for extended operating time.
  • Precise: The sensor shows minimum drift thanks to a very low level of ion depletion in electrolyte.
  • Memosens 2.0 offers extended storage of calibration and process data. These data are the ideal basis for predictive maintenance and can also be used to develop and provide enhanced IIoT services.
  • Safe: Non-contact, inductive, digital signal transmission eliminates errors due to moisture.
  • Cost-efficient: Fast sensor exchange in the field increases process uptime and regeneration extends the sensor lifetime.

Integrated technologies

Memosens technology
Liquiline: cutting-edge transmitter platform
FLEXible answers to individual needs
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Digital pH sensor Memosens CPS31E

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Manufacturer's warranty

Engineered for confidence

Our instruments are designed for long‑lasting performance, precise measurement, and dependable operation in demanding industrial environments. Each product includes a standard manufacturer’s warranty that reflects our commitment to quality and to the trust you place in our solutions.

Should a warranty case occur, the device will be assessed and the applicable remedy will be provided in line with the warranty terms – helping ensure a reliable and efficient resolution and supporting continued operation of your measurement point.

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The manufacturer's warranty and extended warranty are subject to specific conditions. For full details, please refer to the locally applicable General Terms and Conditions (GTC), which can be found on the respective country page of our website.

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Endress+Hauser’s qualified service engineers ensure your measurement devices are commissioned right the first time, delivering application‑aligned accuracy, regulatory compliance, and operational confidence from startup onwards, anywhere in the world.

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Technology
Memosens technology

Memosens 2.0: Cutting-edge sensor technology reloaded

Make life easier, increase process safety and stay connected with Memosens 2.0 digital technology.

Technology

Liquiline: cutting-edge transmitter platform

By choosing the Liquiline platform, you’re effectively choosing to spend less money on stock holding, save installation time and gain operational safety!

Product information

Memosens CPS31E - Digital pH sensor for pH compensation in disinfection processes
Memosens CPS31E digital pH sensor
Specifications
Measuring / Application task pH
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Description

Memosens CPS31E is the expert for pH compensation in disinfection processes. It delivers stable measurement results, ensuring safe swimming pool and drinking water. Thanks to Memosens 2.0 digital technology, CPS31E provides the perfect data basis for predictive maintenance, offers easy operation and more process uptime since it can be calibrated in the laboratory and quickly exchanged on site. The sensor resists moisture and its 3 optional junctions make it suitable for minimum conductivity.

Field of application
  • Drinking water
  • Swimming pool water
  • pH compensation for free chlorine and free bromine measurement
Benefits
  • Reliable: Ceramic junction ensures reliable measurement at low conductivities. For minimum conductivities, 3 junctions are the best choice.
  • Robust: The optional salt storage provides for extended operating time.
  • Precise: The sensor shows minimum drift thanks to a very low level of ion depletion in electrolyte.
  • Memosens 2.0 offers extended storage of calibration and process data. These data are the ideal basis for predictive maintenance and can also be used to develop and provide enhanced IIoT services.
  • Safe: Non-contact, inductive, digital signal transmission eliminates errors due to moisture.
  • Cost-efficient: Fast sensor exchange in the field increases process uptime and regeneration extends the sensor lifetime.
Predecessors
Downloads
Most downloaded
Technical Information (TI)
Memosens CPS31E pH sensor for standard applications in drinking water and swimming pool
water
English version - 03/2021
Download
Operating Instruction (BA)
BA pH sensors CPSx1E, CPFx1E ORP sensors CPSx2E, CPFx2E pH and ORP measurement
English version - 03/2026
Download
Ex Safety Instruction (XA)
XA Memosens pH/ORP sensors pH and ORP measurement
Supplement to: BA01988C, BA02142C
Safety instructions for electrical apparatus in explosion-hazardous
areas
NEPSI Ex ia IIC T3/T4/T6 Ga
NEPSI Ex ia IIC T4/T6 Ga
English version - 11/2024
Download
The CAD Drawings will be available after the configuration.
All downloads
44 Downloads
Technical Information (TI)
Most downloaded
Memosens CPS31E pH sensor for standard applications in drinking water and swimming pool
water
English version - 03/2021
Download
Operating Instruction (BA)
Most downloaded
BA pH sensors CPSx1E, CPFx1E ORP sensors CPSx2E, CPFx2E pH and ORP measurement
English version - 03/2026
Download
Ex Safety Instruction (XA)
XA Memosens pH/ORP sensors pH and ORP measurement
Supplement to: BA01988C, BA02142C
Safety instructions for electrical apparatus in explosion-hazardous
areas
NEPSI Ex ia IIC T3/T4/T6 Ga
NEPSI Ex ia IIC T4/T6 Ga
English version - 11/2024
Download
Ex Safety Instruction (XA)
Memosens pH/ORP sensors pH and ORP measurement
Supplement to BA01988C, BA02142C
Safety instructions for electrical apparatus in explosion-hazardous
areas
UK Ex II 1 G Ex ia IIC T3/T4/T6 Ga
UK Ex II 1G Ex ia IIC T4/T6 Ga
English version - 11/2021
Download
Ex Safety Instruction (XA)
XA Memosens pH/ORP sensors pH and ORP measurement
Supplement to BA01988C, BA02142C
Safety instructions for electrical apparatus for explosion-hazardous areas
ATEX II 1G Ex ia IIC T3/T4/T6 Ga
ATEX II 1G Ex ia IIC T4/T6 Ga
IECEx Ex ia IIC T3/T4/T6 Ga
IECEx Ex ia IIC T4/T6 Ga
English version - 01/2025
Download
Ex Safety Instruction (XA)
XA Memosens pH/ORP sensors pH and ORP measurement
EAC Ex 0Ex ia IIC T3/T4/T6 Ga X
EAC Ex 0Ex ia IIC T4/T6 Ga X
English version - 04/2025
Download
Ex Safety Instruction (XA)
Memosens pH/ORP sensors pH and ORP measurement
Supplement to: BA01988C, BA02142C
Safety instructions for electrical apparatus in explosion-hazardous
areas
NEPSI Ex ia IIC T3/T4/T6 Ga
NEPSI Ex ia IIC T4/T6 Ga
English version - 09/2021
Download
Ex Safety Instruction (XA)
XA Memosens pH/ORP sensors pH and ORP measurement
Safety instructions for electrical apparatus in explosion-hazardous
areas
English version - 11/2024
Download
Ex Safety Instruction (XA)
Memosens pH/ORP sensors pH and ORP measurement
Supplement to BA01988C, BA02142C
Safety instructions for electrical apparatus in explosion-hazardous
areas
KOR Ex ia IIC T3/T4/T6 Ga
KOR Ex ia IIC T4/T6 Ga
English version - 10/2021
Download
Ex Safety Instruction (XA)
Memosens pH/ORP sensors pH and ORP measurement
Safety instructions for electrical apparatus in explosion-hazardous
areas
English version - 04/2021
Download
Ex Safety Instruction (XA)
XA Memosens pH/ORP sensors Safety instructions for electrical apparatus in explosion-hazardous areas
CSA C/US IS Cl. I Div. 1 GP A-D T3/T4/T6 + CSA C/US IS Cl. I Zone 0 AEx ia IIC T3/T4/T6
CSA C/US IS Cl. I Div. 1 GP A-D T4/T6 + CSA C/US IS Cl. I Zone 0 AEx ia IIC T4/T6
CSA C/ US Cl. 1 Div 1&2 GP A-D T6…T3
English version - 05/2026
Download
Ex Safety Instruction (XA)
Memosens pH/ORP sensors pH and ORP measurement
Safety instructions for electrical apparatus in explosion-hazardous
areas
English version - 04/2021
Download
Fields of Activities (FA)
水質分析の専門知識 センサからすべてを備えた
ターンキーソリューションまで
Japanese version - 06/2025
Download
Fields of Activities (FA)
Sensors, transmitters, compact devices and assemblies Experts in Liquid Analysis
English version - 02/2026
Download
Fields of Activities (FA)
Sıvı analizinde uzmanlık Sensörlerden komple anahtar teslim çözümlere
Turkish version - 11/2023
Download
Fields of Activities (FA)
Expertise in liquid analysis From sensors to complete turnkey solutions
English version - 09/2022
Download
Fields of Activities (FA)
Sensoren, Messumformer, Kompaktgeräte and Armaturen Kompetenz in der Flüssigkeitsanalyse
German version - 02/2026
Download
Fields of Activities (FA)
Sensori, trasmettitori, dispositivi compatti e armature Sensori, trasmettitori,
dispositivi compatti e armature
Esperti in materia di analisi dei
liquidi
Italian version - 06/2026
Download
Fields of Activities (FA)
Endress+Hauser 水質分析計ファミリ ラインナップと事例
Japanese version - 03/2017
Download
Competence Brochure (CP)
pH-Messung in Industrieprozessen Auswahl- und Engineering-Hilfe für verschiedene Industriebranchen und
Applikationen
German version - 12/2021
Download
Competence Brochure (CP)
pH 測定セレクションガイド 産業プロセスにおけるpH測定
Japanese version - 06/2026
Download
Competence Brochure (CP)
pH measurement in industrial processes Selection and engineering guide for different industries and
applications
English version - 12/2021
Download
Case Study (CS)
Monitoraggio dell’acqua potabile per grandi eventi - con il pannello di analisi e l’ecosistema Netilion basato su cloud Sui 120 ettari del sito di Goms è stato necessario
fornire acqua potabile di qualità impeccabile ai
30.000 partecipanti al campo scout. Il caldo insolito
e il gran numero di visitatori hanno posto gli
organizzatori di fronte a sfide particolari.
Italian version - 04/2024
Download
Case Study (CS)
Trinkwasser-Überwachung bei Grossveranstaltung Für die 30’000 Teilnehmer des Pfadilagers im BuLa
muss Trinkwasser in einwandfreier Qualität zur
Verfügung gestellt werden. Mit der Netilion-Lösung
kann die Kontrolle zeit- und ortsunabhängig erfolgen.
German version - 10/2022
Download

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Memosens CPS31E - Digital pH sensor for pH compensation in disinfection processes
Memosens CPS31E digital pH sensor

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Spare parts and accessories

further parts
further parts

Kit CPSxx protective caps

further parts
further parts
Order code 71538217

Memoclip label Memosens sensor

Order code 71038228

Memoclip label memosens cable

Order code 71038229

KCL-Electrolyte solution CPY4

Order code CPY4-
Spare parts and accessories

Selection of compatible products

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