TI01601C/07/EN/01.21
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Memosens CPS76E
pH/ORP sensor for process technology

Digital with Memosens 2.0 technology
Application
Process technology and monitoring of processes with:• Rapidly changing pH values• High proportion of electrode poisons such as H2SWith ATEX, IECEx, CSA C/US, NEPSI, Japan Ex and INMETRO approvals for use inhazardous areas Zone 0, Zone 1 and Zone 2.
Your benefits• Simultaneous measurement of pH, ORP and rH value (in rH mode)• Platinum electrode for measuring reference impedance• Newly developed, acrylamide-free gel as bridging electrolyte, sterilizable and very
resistant to chemical corrosion• Suitable for CIP/SIP cleaning, autoclavable• Long service life thanks to poison-resistant reference with ion trap
• Integrated NTC 30K temperature sensor for effective temperature compensation• Glass breakage and blockage detection by measuring:• Resistance of glass membrane• Reference impedance
Other advantages provided by 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 are saved in the sensor• Predictive maintenance can be performed by recording sensor load data in thesensor

Memosens CPS76E

Function and system design
Measuring principle

pH measurement
The pH value is used as a unit of measurement for the acidity or alkalinity of a medium. The
membrane glass of the electrode delivers an electrochemical potential that depends on the pH valueof the medium. This potential is generated by the selective accumulation of H+ ions on the outerlayer of the membrane. As a result, an electrochemical boundary layer with an electrical potential
difference forms at this point. An integrated Ag/AgCl reference system serves as the requiredreference electrode.
The measured voltage is converted to the corresponding pH value using the Nernst equation.
ORP measurement
The ORP potential is a unit of measurement for the state of equilibria between oxidizing andreducing components of a medium. The ORP is measured using a platinum or gold electrode. Similarto pH measurement, an integrated Ag/AgCl reference system is used as a reference electrode.
rH measurement
The rH value is defined as the negative logarithm of partial pressure of hydrogen in a solution. ThepH value and ORP value of a solution must be measured simultaneously to calculate the rH value.
The value is calculated using the following equation:rH = 2 . (mV/S) + 2 pH
pH

Measured pH valuemV

Measured ORP value in mV + 207 mV (Ag/AgCl system)

S

Slope of pH electrodeThe rH value is an indicator of the oxidation or reducing power of a process solution. The rH scaleruns from 0 to 42.

Measuring systemrH values

Process medium

0 to 9Strong reducing power

9 to 17

Weak reducing power

17 to 25

Undetermined medium

25 to 34

Weak oxidizing power

34 to 42

Strong oxidizing power

A complete measuring system comprises:• pH/ORP sensor CPS76E• Memosens data cable CYK10 or CYK20• Transmitter, e.g. Liquiline CM44, Liquiline CM42
• Assembly• Immersion assembly, e.g. Dipfit CPA111• Flow assembly, e.g. Flowfit CPA250• Retractable assembly, e.g. Cleanfit CPA871• Permanent installation assembly, e.g. Unifit CPA842
Additional options are available depending on the application:
Automatic cleaning and calibration system, e.g. Liquiline Control CDC90

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41
32A0025757

Endress+Hauser

1Example of a measuring system for pH measurement

123
4

Retractable assembly Cleanfit CPA871
pH/ORP sensor CPS76E
Memosens data cable CYK10
Liquiline M CM42 two-wire transmitter for hazardous areas

3

Memosens CPS76E

Communication and dataprocessing

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)• Offset of integrated temperature sensor• Offset of ORP measurement• Number of calibrations• Calibration history• Serial number of the transmitter used to perform the last calibration or adjustment• Application data
• Temperature application range• pH application range• ORP application range• Date of initial commissioning• Maximum temperature value• Hours of operation under extreme conditions• Number of sterilizations• CIP counter
The data listed above can be displayed with Liquiline CM42, CM44x, and Memobase Plus CYZ71D.

Dependability

Reliability
Easy handlingSensors with Memosens technology have integrated electronics that store calibration data and otherinformation (e.g. total hours of operation or operating hours under extreme measuring conditions).
Once the sensor has been connected, the sensor data are transferred automatically to the transmitterand 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 ofthe calibration.
• Pre-calibrated sensors can be replaced quickly and easily, resulting in a dramatic increase in theavailability of the measuring point.
• Thanks to the availability of the sensor data, maintenance intervals can be accurately defined andpredictive maintenance is possible.
• The sensor history can be documented on external data carriers and evaluation programs, e.g.
Memobase Plus CYZ71D,.
• The saved application data of the sensor can be used to determine the continued use of the sensor
in a targeted manner.
Integrity
Data security thanks to digital data transmission
Memosens technology digitizes the measured values in the sensor and transmits the data to thetransmitter via a non-contact connection that is free from potential interference. The result:• If the sensor fails or there is an interruption in the connection between the sensor and transmitter,
this is reliably detected and reported.
• The availability of the measuring point is reliably detected and reported.

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Memosens CPS76E

SafetyMaximum 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:• No corrosion at the connection• Measured values cannot be distorted by moisture• The transmitter is galvanically decoupled from the medium. Issues concerning "symmetrical highimpedance" or "asymmetry" or the type of impedance converter are a thing of the past.
• Electromagnetic compatibility (EMC) is guaranteed by screening measures for the digitaltransmission of measured values.
• Intrinsically safe electronics mean operation in hazardous areas is not a problem. Complete
flexibility thanks to individual Ex approvals for all components, such as sensors, cables andtransmitters.

Input
Measured variable• pH value• ORP• rH value• Temperature

Measuring range

ORP: –1 500 to 1 500 mV
Application B• pH: 0 to 14• Temperature: 0 to 140 °C (32 to 284 °F)
Application H• pH: 0 to 12• Temperature: 0 to 140 °C (32 to 284 °F)
Pay attention to the operating conditions in the process.

Power supply
Electrical connection

GY GNDYE Com B
GN Com A
WH –BN +EY/NGA0024019

2

Measuring cable CYK10 or CYK20‣ Connect the Memosens measuring cable, e.g. CYK10 or CYK20 to the sensor.
For further information on cable CYK10, see BA00118C

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5Memosens CPS76E

Performance characteristics
Reference system

TB and TU reference system:
TP reference system:

Ag/AgCl reference lead with ion trap, bridging electrolyte: gel KCl,
3M, AgCl-free
Ag/AgCl reference lead with ion trap, bridging electrolyte: gel KCl,
3M, AgCl-free, pressurized 7 bar (102 psi) (absolute); display via
pressure indicator

Installation
Orientation• Do not install the sensors upside-down.
• The angle of inclination from the horizontal must be at least 15°.
NOTICE
Angle of inclination of the sensor less than 15°
An air bubble forms in the glass bulb and there is then no guarantee that the pH membrane iscompletely covered with inner electrolyte!
‣ Select the installation angle of the sensor so that it does not drop below 15°.

A15°15°
B

A0028039

3A
B

Installation angle at least 15° from the horizontal
Permitted orientation
Forbidden orientation

Orientation of sensors for upside-down installation:• The sensors are suitable for upside-down installation in accordance with the order code for"Reference system".
• Install the sensors at any angle.

360°

A0028040

4

For detailed installation instructions for the assembly: refer to the Operating Instructions of theassembly used.

Installation instructions
1.

6

Any installation angle

Before screwing in the sensor, make sure the assembly thread, the O-rings and the sealing
surface are clean and undamaged and that the thread runs smoothly.

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Memosens CPS76E

2.

Screw in the sensor and tighten by hand with a torque of 3 Nm (2.21 lbf ft) (specifications only
apply if installing in Endress+Hauser assemblies).
For detailed information on removing the moistening cap, see BA02142C

Environment
Ambient temperature range

NOTICE
Risk of damage from frost!
‣ Do not use the sensor at temperatures below .

Storage temperature

0 to 50 °C (32 to 122 °F)

Degree of protection

IP 68 (10 m (33 ft) water column, 25 °C (77 °F), 45 days, 1 M KCl)

Electromagneticcompatibility (EMC)

Interference emission and interference immunity as per:• EN 61326-1:2013• EN 61326-2-3:2013• NAMUR NE21:2017

Process
Process temperature range

Applications B and H: 0 to 140 °C (32 to 284 °F)
Version TB:
Version TU, TP (pressurizedreference):

Process pressure range

LCAUTION
Pressurization of sensor due to prolonged use under increased process pressure
Possibility of sudden rupture and injury from glass splinters!
‣ Avoid fast heating of these pressurized sensors if they are used under reduced process pressureor under atmospheric pressure.
‣ When handling these sensors, always wear protective goggles and appropriate protective gloves.
Application B:
Application H

Conductivity

Endress+Hauser

0 to 140 °C (32 to 284 °F)
0 to 140 °C (32 to 284 °F) (140 °C (284 °F) only for sterilization)
Maximum 100 °C (212 °F) in continuous operation due toincreasing pressure loss at T > 100 °C (212 °F)

0.8 to 14 bar (11.6 to 203 psi) absolute
0.8 to 7 bar (11.6 to 101.5 psi) absolute

10 μS/cm (at atmospheric pressure, without flow) (minimized flow; pressure and temperature mustremain constant)

7Memosens CPS76E

Pressure/temperature
ratings[psi] p [bar]2031741412145
116
87
58

10864

29

200

B

H
x
020

40

60

80

100120

140

32

68

104

140

176

212

248

284

[°C]
T
[°F]
A0039291-EN

5B
H
x

Pressure/temperature ratings
Application B
Application H
Atmospheric pressure

Mechanical construction

50(1.97)

Design, dimensions

1120 / 225 / 360 / 425(4.72 / 8.86 / 14.17 / 16.73)

2345678

Ø 11.9 (0.47)
A0045817

612345678Weight

8CPS76E. Engineering unit: mm (in)Memosens plug-in head with process connection
O-ring with thrust collar
Reference with ion trap
ORP measuring element
Ceramic junction
Temperature sensor
Ag/AgCl reference lead
pH glass membrane

Installed length

120 mm (4.72 in)

225 mm (8.86 in)

360 mm (14.17 in)

425 mm (16.73 in)

Weight40 g (1.4 oz)

60 g (2.1 oz)

90 g (3.2 oz)

100 g (3.5 oz)

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Memosens CPS76E

Materials

Sensor shaft
pH membrane glass
Metal lead
Open aperture
ORP measuring element
O-ringProcess coupling
NameplateGlass to suit process
Type B
Type N
Ag/AgCl
Ceramic junction, zirconium dioxide
Platinum
FKM
PPS fiber-glass reinforced
Ceramic metal oxide

Temperature sensor

NTC 30K

Plug-in head

Memosens plug-in head for digital, non-contact data transmission, pressure resistance
16 bar (232 psi) (relative)

Process connections

Pg 13.5

Certificates and approvals
 markThe product meets the requirements of the harmonized European standards. As such, it complies
with the legal specifications of the EU directives. The manufacturer confirms successful testing of theproduct by affixing to it the  mark.

Ex approval

ATEX
II 1G Ex ia IIC T3/T4/T6 Ga
IECEx
Ex ia IIC T3/T4/T6 Ga
NEPSI
Ex ia IIC T3/T4/T6 Ga
CSA C/US• IS CL I DIV 1, GP A, B, C, D Ex ia IIC T3/T4/T6• CL 1 Zone 0, AEx ia IIC T3/T4/T6 Ga
Japan ExEx ia IIC T3/T4/T6 Ga
INMETROEx ia IIC T3/T4/T6 Ga
Hazardous area versions of the digital sensors with Memosens technology are indicated by ared/orange ring on the plug-in head.
Pay attention to the instructions for Memosens data cable CYK10 and transmitters CM82 andCM42.

Additional certification

TÜV certificate for Memosens plug-in head
Pressure resistance 16 bar (232 psi) relative, minimum three times the safety pressure
EAC
The product has been certified according to guidelines TP TC 004/2011 and TP TC 020/2011 which
apply in the European Economic Area (EEA). The EAC conformity mark is affixed to the product.

Ordering information
Product page

Endress+Hauser

www.endress.com/cps76e

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Memosens CPS76E

Product Configurator

On the product page there is a Configure button to the right of the product image.
1.

Click this button.
 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 on the rightabove the selection window.
For many products you also have the option of downloading CAD or 2D drawings of theselected product version. Click the CAD tab for this and select the desired file type using
picklists.

Scope of delivery

The delivery comprises:• Sensor in the version ordered• Operating Instructions• Safety instructions for the hazardous area (for sensors with Ex approval)

Accessories
The following are the most important accessories available at the time this documentation wasissued.

‣ For accessories not listed here, please contact your Service or Sales Center.
Device-specific accessories

Assemblies
Unifit CPA842• Installation assembly for food, biotechnology and pharmaceutics• With EHEDG and 3A certificate• Product Configurator on the product page: www.endress.com/cpa842
Technical Information TI01367C
Cleanfit CPA875• Retractable process assembly for sterile and hygienic applications• For in-line measurement with standard sensors with 12 mm diameter, e.g. for pH, ORP, oxygen• Product Configurator on the product page: www.endress.com/cpa875
Technical Information TI01168C
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
Cleanfit CPA871• Flexible process retractable assembly for water, wastewater and the chemical industry• For applications with standard sensors with 12 mm diameter• Product Configurator on the product page: www.endress.com/cpa871
Technical Information TI01191C
Cleanfit CPA450• Manual retractable assembly for installing sensors with a diameter of 12 mm and a length of
120 mm in tanks and pipes• Product Configurator on the product page: www.endress.com/cpa450
Technical Information TI00183C

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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 ofthe medium from the environment• Product Configurator on the product page: www.endress.com/cpa474
Technical Information TI00345C
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
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 sensors and sensor cable with TOP68 coupling• Product Configurator on the product page: www.endress.com/cpa640
Technical Information TI00246C
Buffer solutions
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) or to standard reference material of NIST (NationalInstitute of Standards and Technology) according to DIN 19266 by a laboratory accredited by theDAkkS (German accreditation body) according to DIN 17025.
Product Configurator on the product page: www.endress.com/cpy20
ORP buffer solution CPY3
• 220 mV, pH 7
• 468 mV, pH 0.1
Product Configurator on the product page: www.endress.com/cpy3
Measuring cable
Memosens data cable CYK10• For digital sensors with Memosens technology• Product Configurator on the product page: www.endress.com/cyk10
Technical Information TI00118C
Memosens laboratory cable CYK20• For digital sensors with Memosens technology• Product Configurator on the product page: www.endress.com/cyk20

Endress+Hauser

11*71526117*
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