Calibrating Cr Conductivity Sensors; Notes; General Information; Calibration Methods For Cr Conductivity Sensors (Conductive) - JUMO AQUIS touch P Installation Instructions Manual

15.1

Notes

15.2

General information

15.2.1

Calibration methods for CR conductivity sensors (conductive)

Rel. cell constant
Temperature coefficient

15 Calibrating CR conductivity sensors

WARNING!
During the calibration, the relays and analog output signals assume the config-
ured states!
The calibration of CR sensors is based on measurements in test solutions with
a defined electrolytic conductivity. Since the electrolytic conductivity of liquids is
temperature dependent, the temperature of the test solution must be sensed.
This requires either manual entry or measurement with the aid of a temperature
sensor.
The deviation from the nominal cell constant of a CR sensor is described by the
relative cell constant. The rel. cell constant is determined by making a measure-
ment in a test solution with a defined conductivity.
The temperature coefficient is a measure of the temperature dependence of the
electrolytic conductivity of a liquid. Is used to compensate for the effect of tem-
perature when measuring the electrolytic conductivity. When making a tempera-
ture-compensated conductivity measurement, the measuring value of the
conductivity is always given on the basis of the fixed, preset reference tempera-
ture. With the aid of the temperature coefficient, the value of the electrical con-
ductivity at the reference temp. is calculated from the current values of
conductivity and temperature measured for the liquid and then displayed.
Reference temp. is set in the configuration of the individual CR analysis input.
v Chapter 9.5.4 "CR/Ci analysis inputs (conductive/inductive conductivity)",
Page 104
The temperature coefficient is determined from 2 measurements in a test solu-
tion at different temperatures (reference and operation temp.).
NOTE!
If the temperature coefficient of a sample solution is known, it can be entered
directly.
v Chapter 11.2.1 "General procedure for calibration", Page 15
35