Ceraliquid CPS41D and CPS41

2

Endress+Hauser

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 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.

Measuring system

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

• pH electrode CPS41D or CPS41

• Transmitter, e.g. Liquiline CM42, CM44x/R, Mycom153, Liquisys M CPM2x3

• Memosens data cable CYK10 or CYK20 for Memosens sensors or CPK9 for analog sensors

• Immersion, flow or retractable assembly, e.g. Unifit CPA442

• Electrolyte vessel CPY7

2

3

1

5

4

A0027761

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Example of a measuring system for pH measurement

1

Electrolyte vessel CPY7

2

Liquiline M CM42 two-wire transmitter for hazardous area

3

Memosens data cable CYK10

4

pH electrode CPS41D

5

Process assembly Unifit CPA442