Endress+Hauser CPS71D Specifications

TI00245C/07/EN/15.15
71299932

Products Solutions Services

Technical Information

Ceragel CPS71D and CPS71

pH single-rod measuring cells, analog or with
digital Memosens technology

For chemical process, hygienic and sterile
applications with an ion trap for poison-resistant
reference

Application

• Aggressive chemical and hygienic applications
– Chemical industry
– Foods
– Fermenters
– Biotechnology
– Pharmaceutical industry

• Process technology and monitoring of processes with:
– Rapidly changing pH values
– High proportion of electrode poisons such as H2S

With ATEX, FM and CSA approval for use in hazardous areas

Your benefits

• Poison-resistant reference with ion trap, resulting in a very long service life,
bridging electrolyte free of silver ions

• TP version with pressurized reference, for chemical and fermentation processes

• TU version for upside-down installation, solidified gel in the internal reference lead

• Integrated temperature sensor for effective temperature compensation

• Suitable for CIP/SIP cleaning, autoclavable

• Biocompatibility: reference electrolyte with certified non-cytotoxic gel

• Acrylamide-free reference and bridging electrolyte

Other advantages of Memosens technology

• Maximum process safety thanks to non-contact, inductive signal transmission

• Data security thanks to digital data transmission

• Very easy to use as sensor data saved in the sensor

• Recording of sensor load data in the sensor enables predictive maintenance with
the Memobase Plus CYZ71D

Function and system design

3

4

1

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Ceragel CPS71D and CPS71

Measuring principle

Measuring system

pH measurement

The pH value is used as a unit of measurement for the acidity or alkalinity of a liquid medium. The
membrane glass of the electrode supplies an electrochemical potential which is dependent upon the
pH value of the medium. This potential is generated by the selective penetration of H+ ions through
the outer layer of the membrane. An electrochemical boundary layer with an electric potential forms
at this point. An integrated Ag/AgCl reference system serves as the required reference electrode.
The transmitter converts the measured voltage into the corresponding pH value using the Nernst
equation.

A complete measuring system consists of the following components at least:

• pH electrode CPS71D or CPS71

• Transmitter, e.g. Liquiline CM42, CM44x/R, Mycom S CPM153, Liquisys M CPM2x3

• Memosens data cable CYK10 for Memosens sensors or CPK9 for analog sensors

• Immersion, flow or retractable assembly, e.g. Cleanfit CPA871/875

A0025757

 1 Example of a measuring system for pH measurement

1 Retractable assembly Cleanfit CPA871
2 pH electrode CPS71D
3 Memosens data cable CYK10
4 Liquiline M CM42 two-wire transmitter for hazardous area

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Ceragel CPS71D and CPS71

Communication and data processing CPS71D

Communication with the transmitter

Always connect digital sensors with Memosens technology to a transmitter with Memosens
technology. Data transmission to a transmitter for analog sensors is not possible.

Digital sensors can store measuring system data in the sensor. These include the following:

• Manufacturer data
– Serial number
– Order code
– Date of manufacture

• Calibration data
– Calibration date
– Slope at 25 °C (77 °F)
– Zero point at 25 °C (77 °F)
– Temperature offset
– Number of calibrations
– Serial number of the transmitter used to perform the last calibration

• Operating data
– Temperature application range
– pH application range
– Date of initial commissioning
– Maximum temperature value
– Hours of operation under extreme conditions
– Number of sterilizations
– Resistance of glass membrane

You can display the abovementioned data using the Liquiline CM44x, CM42 and Memobase Plus
CYZ71D.

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Dependability

Ceragel CPS71D and CPS71

Reliability

Integrity Data security thanks to digital data transmission

Safety

Easy handling

Sensors with Memosens technology have an integrated electronics unit that stores calibration data
and other information (e.g. total operating hours and operating hours under extreme measuring
conditions). Once the sensor has been connected, the sensor data are transferred automatically to
the transmitter and used to calculate the current measured value. As the calibration data are stored
in the sensor, the sensor can be calibrated and adjusted independently of the measuring point. The
result:

• Easy calibration in the measuring lab under optimum external conditions increases the quality of
the calibration.

• Pre-calibrated sensors can be replaced quickly and easily, resulting in a dramatic increase in the
availability of the measuring point .

• Maintenance intervals can be defined based on all stored sensor load and calibration data and
predictive maintenance is possible.

• The sensor history can be documented using external storage media and evaluation programs, e.g.
Memobase Plus CYZ71D. Thus, the current application of the sensors can be made to depend on
their previous history.

Memosens technology digitizes the measured values in the sensor and transmits the data to the
transmitter using a non-contact connection that is free from potential interference. The result:

• Automatic error message if sensor fails or connection between sensor and transmitter is
interrupted

• Immediate error detection increases measuring point availability

Maximum process safety

With inductive transmission of the measured value using a non-contact connection, Memosens
guarantees maximum process safety and offers the following benefits:

• All problems caused by moisture are eliminated:
– Plug-in connection free from corrosion
– Measured values cannot be distorted by moisture.
– Can even be connected under water

• The transmitter is galvanically decoupled from the medium. Issues concerning "symmetrical high­impedance" or "asymmetry" or an impedance converter are a thing of the past.

• EMC safety is guaranteed by screening measures for the digital transmission of measured values.

• Intrinsically safe electronics mean operation in hazardous areas is not a problem.

4 Endress+Hauser

Ceragel CPS71D and CPS71

Input

Measured variables

Measuring range

pH value

Temperature

Electrode version TB, TC:
pH: 0 to 14 pH
Temperature: • 0 to 140 °C (32 to 284 °F)

• 0 to 135 °C (32 to 275 °F) for sensors with Ex approval and analog
sensors

Electrode version TP (pressurized reference):
pH: 0 to 12 pH
Temperature: • 0 to 140 °C (32 to 284 °F)

(140 °C (284 °F) only for sterilization)

• 0 to 135 °C (32 to 275 °F) for sensors with Ex approval and analog
sensors
(135 °C (275 °F) only for sterilization)

• Max. 100 °C (212 °F) in continuous operation due to increasing
pressure loss at T > 100 °C (212 °F)

Electrode version TU:
pH: 0 to 14 pH
Temperature: • 0 to 140 °C (32 to 284 °F)

(140 °C (284 °F) only for sterilization)

• 0 to 135 °C (32 to 275 °F) for sensors with Ex approval and analog
sensors
(135 °C (275 °F) only for sterilization)

• Max. 100 °C (212 °F) in continuous operation due to liquefaction of
gel-based inner electrolyte at T > 100 °C (212 °F)

Please note the process operating conditions.

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Installation

15°

15°

A

B

360°

Ceragel CPS71D and CPS71

Installation instructions

• Electrode versions TB, TC and TP
Do not install the electrodes upside down. The angle of inclination must be at least 15° from the
horizontal. A smaller inclination angle is not permitted as it could cause an air bubble to form in
the glass sphere and prevent the inner electrolyte from completely wetting the pH diaphragm.

• Electrode version TU
This electrode is suitable for upside-down installation. You can install it at any angle.

NOTICE

Before screwing in the electrode, make sure the assembly threaded connection is clean and
runs smoothly.

Screw in the electrode finger-tight (3 Nm)! (Data apply only if installing with

‣

Endress+HauserOPA assemblies.)
Make sure to follow the installation instructions in the Operating Instructions of the used

‣

assembly.

Installation instructions for electrode version TP

 2 Installation of electrode versions TB, TC, TP;

installation angle at least 15° from the horizontal

A Permitted orientation
B Forbidden orientation

CAUTION

L

A0024316

 3 Installation of electrode version TU; any

installation angle

A0024597

Sudden rupture and flying glass splinters from the glass electrode with pressurized reference
(approx. 7 bar abs. internal pressure)

Always wear protective goggles when working with these electrodes

‣

Be particularly careful when removing the silicone seal on the reference junction. Here, a knife is

‣

used to activate the electrode for measuring operation.

Before commissioning the electrode, you must remove the silicone seal from the junction. The pH
value can only be measured properly once the seal has been removed.

To do this, proceed as follows:

1. Using the knife supplied, completely remove the silicone seal from the junction.

2. To ensure optimum accuracy with this as with all pH electrodes, place the electrode in a
calibration standard buffer solution with a pH of between 4 and 9 for 15-20 minutes prior to
calibration.

3. Put the electrode into operation.

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Ceragel CPS71D and CPS71

A

0

40

80

50

100

150

200 250

275

120

159

300

212

B

C

400 20 60 80 100

0

4

6

8

10

2

[°C]

T

[°F]

[psi] p [bar]

12

14

120

135

140

284

D

1

203

11

7

101

15

E

Environment

Ambient temperature range

Storage temperature

Degree of protection

Process temperature

Process pressure (absolute)

NOTICE

Risk of damage due to frost

The sensor must not be used if the temperature drops below –15 °C (5 °F).

‣

0 to 50 °C (32 to 122 °F)

IP 68: Memosens plug-in head, (10 m (33 ft) water column, 25 °C (77 °F), 45 days, 1 M KCl)
IP 68: ESA plug-in head (1 m (3.3 ft) water column, 50 °C (122 °F), 168 h)
IP 67: GSA plug-in head (with closed connector system)

Process

Electrode version TB, TC:

Electrode version TP, TU: 0 to 100 °C (32 to 212 °F)

Electrode version TB, TC:
Electrode version TU: 1 to 11 bar (15 to 159 psi)
Electrode version TP: 1 to 7 bar (15 to 101 psi)

Minimum 0.8 bar abs. is possible. Be aware of quick KCl consumption.

0 to 140 °C (32 to 284 °F)
0 to 135 °C (32 to 275 °F) for sensors with Ex approval and analog
sensors

(sterilizable up to 140 °C (284 °F) / 135 °C (275 °F) for sensors with
Ex approval and analog sensors)

1 to 14 bar (15 to 203 psi)

CAUTION

L

Pressurization of sensor due to prolonged use under increased process pressure

Risk of injury from glass breakage

Avoid excessive heating of such sensors if using them under reduced process pressure or under

‣

atmospheric pressure.
When handling such sensors, wear protective goggles and suitable gloves.

‣

Pressure-temperature ratings

A0025785

 4 Pressure-temperature ratings

Minimum conductivity

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A Version TB, TC
B Version TB, TC with Ex approval and analog sensors
C Version TU
D Version TP
E Atmospheric pressure

10 μS/cm (at atmospheric pressure, without flow)

Ceragel CPS71D and CPS71

120, 225, 360, 425 (4.72, 8.86, 14.2, 16.7)

12 (0.47)

1

2

3

4

5
6

7

120, 225, 360, 425 (4.72, 8.86, 14.2, 16.7)

12 (0.47)

1

2

3

4

5

6

7

8

9

pH range

Design, dimensions CPS71D

Electrode version TB, TC, TU: 0 to 14 pH
Electrode version TP: 0 to 12 pH

NOTICE

Risk of damage to electrode

Never use the electrode outside of the listed specifications!

‣

Mechanical construction

A0019102

 5 CPS71D with Memosens plug-in head, TB

1 Memosens plug-in head
2 Viton O-ring with thrust collar
3 Ag/AgCl reference lead with ion trap
4 Junction
5 Temperature sensor
6 Ag/AgCl internal reference lead - pH
7 pH glass membrane

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 6 CPS71D with Memosens plug-in head, TP

1 Memosens plug-in head
2 Viton O-ring with thrust collar
3 Spacer
4 Pressure indicator with air bubble
5 Ag/AgCl reference lead with ion trap
6 Junction
7 Temperature sensor
8 Ag/AgCl internal reference lead - pH
9 pH glass membrane

A0019104

Ceragel CPS71D and CPS71

12 (0.47)

120, 225, 360, 425 (4.72, 8.86, 14.2, 16.7)

1

2

3

4

5
6

120, 225, 360, 425 (4.72, 8.86, 14.2, 16.7)

12 (0.47)

1

2

3

4

5
6
7

Design, dimensions CPS71

 7 CPS71 with GSA plug-in head, TB

1 GSA electrode plug-in head, Pg 13.5
2 Viton O-ring with thrust collar
3 Ag/AgCl reference lead with ion trap
4 Junction
5 Ag/AgCl internal reference lead - pH
6 pH glass membrane

A0019105

 8 CPS71 with ESA plug-in head, TC

1 ESA electrode plug-in head, Pg 13.5
2 Viton O-ring with thrust collar
3 Ag/AgCl reference lead with ion trap
4 Junction
5 Temperature sensor
6 Ag/AgCl internal reference lead - pH

A0019106

7 pH glass membrane

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Ceragel CPS71D and CPS71

12 (0.47)

120, 225, 360, 425 (4.72, 8.86, 14.2, 16.7)

1

2

3

4

5

6

7

8

9

Weight

Materials

Process connection

Temperature sensor

A0019101

 9 CPS71 with ESA plug-in head, TP

1 ESA electrode plug-in head, Pg 13.5
2 Viton O-ring with thrust collar
3 Spacer
4 Pressure indicator with air bubble
5 Ag/AgCl reference lead with ion trap
6 Junction
7 Temperature sensor
8 Ag/AgCl internal reference lead - pH
9 pH glass membrane

0.1 kg (0.22 lbs) for a length of 120 mm (4.72 inch)

Electrode shaft:

Glass to suit process
pH membrane glasses: Type B
Metal lead: Ag/AgCl
Diaphragm: Ceramic, sterilizable and autoclavable
Reference and bridging electrolyte gel: Acrylamide-free

Pg 13.5

CPS71D:

NTC30K

CPS71: Pt100, Pt1000

Plug-in heads

CPS71D:

Memosens plug-in head for digital, non-contact data transmission, 17 bar abs.
(246 psi), Ex or non-Ex

10 Endress+Hauser

CPS71:

ESA: Threaded plug-in head Pg 13.5, TOP68, 17 bar abs. (246 psi), Ex
GSA: Threaded plug-in head Pg 13.5, non-Ex

Ceragel CPS71D and CPS71

Detail A

Detail A

Reference system

Electrode version TB, TC: Ag/AgCl reference lead with ion trap, reference and bridging

electrolyte 3 M KCl, acrylamide-free, non-cytotoxic

Electrode version TP: Ag/AgCl reference lead with ion trap, reference and bridging

electrolyte 3 M KCl, acrylamide-free, non-cytotoxic, pressurized ion
trap 7 bar abs.; indicated by pressure indicator (→  10).

Electrode version TU: Ag/AgCl reference lead with ion trap, reference and bridging

electrolyte 3 M KCl, acrylamide-free

A0025917

 10 Pressure indicator of electrode version TP

Certificates and approvals

Ex approval CPS71D and CPS71 (ESA)

Biocompatibility

TÜV certificate for Memosens and ESA plug-in head

Electromagnetic compatibility CPS71D

ATEX/NEPSI

II 1G Ex ia IIC T3/T4/T6 Ga

FM/CSA

IS/NI CL. I. Div 1, Group A-D

Hazardous area versions of the digital sensors with Memosens technology are indicated by a
red-orange ring in the plug-in head.

Cytotoxicity tested to:

• ISO 10993-5:2009

• USP 37: 2014, chapter <87> for reference electrolyte gel

Pressure resistance 16 bar rel. (232 psi), minimum three times the safety pressure

Interference emission and interference immunity as per EN 61326: 2012

Endress+Hauser 11

Ordering information

Ceragel CPS71D and CPS71

Product page

Product Configurator

Scope of delivery

Assemblies

www.endress.com/cps71d

www.endress.com/cps71

The navigation area is located on the right of the product page.

1. Under "Device support" click "Configure your selected product".
 The Configurator opens in a separate window.

2. Select all the options to configure the device in line with your requirements.
 In this way, you receive a valid and complete order code for the device.

3. Export the order code as a PDF or Excel file. To do so, click the appropriate button at the top of
the screen.

The scope of delivery includes:

• Sensor in the version ordered

• Technical Information

Accessories

The following are the most important accessories available at the time this documentation was
issued. For accessories not listed here, please contact your service or sales office.

Cleanfit CPA472D

• Robust retractable assembly for pH, ORP and other industrial sensors

• Heavy-duty version made of durable materials

• For manual or pneumatic, remote-controlled operation

• Product Configurator on the product page: www.endress.com/cpa472d
Technical Information TI00403C

Cleanfit CPA871

• Flexible process retractable assembly for water, wastewater and the chemical industry

• For applications with standard 12mm sensors

• Product Configurator on the product page: www.endress.com/cpa871
Technical Information TI01191C

Cleanfit CPA875

• Retractable process assembly for sterile and hygienic applications

• For in-line measurement with standard 12 mm sensors for parameters such as pH, ORP and

oxygen

• Product Configurator on the product page: www.endress.com/cpa875
Technical Information TI01168C

Cleanfit CPA450

• Manual retractable assembly for installing 120 mm sensors in tanks and pipes

• Product Configurator on the product page: www.endress.com/cpa450
Technical Information TI00183C

Cleanfit CPA471

• Compact stainless steel retractable assembly for installation in tanks and pipes, for manual or

pneumatically remote-controlled operation

• Product Configurator on the product page: www.endress.com/cpa471
Technical Information TI00217C

12 Endress+Hauser

Ceragel CPS71D and CPS71

Cleanfit CPA472

• Compact plastic retractable assembly for installation in tanks and pipes

• For manual or pneumatic, remote-controlled operation

• Product Configurator on the product page: www.endress.com/cpa472
Technical Information TI00223C

Cleanfit CPA473

• Stainless steel process retractable assembly with ball valve shutoff for particularly reliable

separation of the medium from the environment

• Product Configurator on the product page: www.endress.com/cpa473
Technical Information TI00344C

Cleanfit CPA474

• Plastic process retractable assembly with ball valve shutoff for particularly reliable separation of

the medium from the environment

• Product Configurator on the product page: www.endress.com/cpa474
Technical Information TI00345C

Unifit CPA442

• Installation assembly for food, biotechnology and pharmaceutics

• With EHEDG and 3A certificate

• Product Configurator on the product page: www.endress.com/cpa442
Technical Information TI00306C

Dipfit CPA111

• Immersion and installation assembly made of plastic for open and closed vessels

• Product Configurator on the product page: www.endress.com/cpa111
Technical Information TI00112C

Dipfit CPA140

• pH/ORP immersion assembly with flange connection for very demanding processes

• Product Configurator on the product page: www.endress.com/cpa140
Technical Information TI00178C

Flowfit CPA240

• pH/ORP flow assembly for processes with stringent requirements

• Product Configurator on the product page: www.endress.com/cpa240
Technical Information TI00179C

Flowfit CPA250

• Flow assembly for pH/ORP measurement

• Product Configurator on the product page: www.endress.com/cpa250
Technical Information TI00041C

Ecofit CPA640

• Set comprising adapter for 120 mm pH/ORP electrodes and sensor cable with TOP68 coupling

• Product Configurator on the product page: www.endress.com/cpa640
Technical Information TI00246C

Flexdip CYA112

• Immersion assembly for water and wastewater

• Modular assembly system for sensors in open basins, channels and tanks

• Product Configurator on the product page: www.endress.com/cya112
Technical Information TI00432C

Endress+Hauser 13

Ceragel CPS71D and CPS71

Buffer solutions

Measuring cable

High-quality buffer solutions from Endress+Hauser - CPY20

The secondary buffer solutions have been referenced to primary reference material of the PTB
(German Federal Physico-technical Institute) and to standard reference material of NIST (National
Institute of Standards and Technology) according to DIN 19266 by a DKD (German Calibration
Service) accredited laboratory.
Product Configurator on the product page: www.endress.com/cpy20

CYK10 Memosens data cable

• For digital sensors with Memosens technology

• Product Configurator on the product page: www.endress.com/cyk10
Technical Information TI00118C

CPK9

• Terminated measuring cable for connecting analog sensors with TOP68 plug-in head

• Selection in accordance with product structure
For more information and to order, please contact your sales office.

CPK1

For pH/ORP electrodes with GSA plug-in head

Ordering information is available from your sales office or at www.endress.com.

14 Endress+Hauser

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