Ecolab MULTRONIC Manuel Technique page 36

The temperature compensation factor Tka is specified with the temperature coefficient
function.
Value range: 0.00 %/K to 5.00 %/K
NOTE
If the temperature coefficient of the material under analyses is not known, the following
procedure can be employed:
Set Tkα to 0
-
Bring material under analysis up to a reference temperature of 25 °C
-
Record conductivity
-
Bring material under analysis up to operating temperature
-
Record conductivity
-
Calculate the temperature coefficient according to the following formula:
-
Tkα = Temperature compensation factor in %/K
κT
= Conductivity value at operating temperature
κ25 = Conductivity value at 25 °C (Reference temperature)
T = Operating temperature
K = Thermodynamic temperature
Table showing approximated Coefficients of Temperature Tkα for 25°C for selected
solutions up to a maximum concentration of 5 %wt.:
Group
Salts
Alkalis
Acids
The modul selection function can be used to return to the measurement parameter
module selection.
417101802_Anhang02_LF_konduktiv.doc
Conductivity Measuring Module (contact measurement)
The accuracy of measurement depends to a great extent on a correctly adjusted
Coefficient of Temperature Tkα.
The Coefficient of Temperature is dependent on the solution used, and on its
concentration and temperature.
α
=
Tk
Solution
Tkα for 25° C [%/K]
NaCl
NaOH
HCl
HNO
3
H SO
2 4
κ
⎛ ⎞
T
−
⎜ ⎟
1
κ
⎝ ⎠
[ ]
25
•
100 %
− °
T 25 C
2.1
1.8
1.5
1.3
1.0
- 36 - Rev.: 05-07/10