wtw inoLab pH/ION Level 2 Operating Manual page 35

Preparatory
activities
Calibration
Perform the following preparatory activities:
1 Switch on the instrument by pressing
2 Connect the electrode to the instrument.
3 Connect a temperature probe to the instrument in
order to notice whether there are temperature diffe-
rences too high while calibrating.
4 Keep the standard solutions ready.
5 Adjust the temperature of the solutions.
Note
For calibration, use tempered standard solutions with a tem-
perature that differs by maximum
ture of the test sample.
Use two or three different standard solutions out of the fol-
lowing range. For the three point calibration, the standards
must be selected in increasing or decreasing order.
Parameter Values [mg/l]
Std 1 0.01; 0.02; 0.05; 0.1; 0.2; 0.5; 1; 2; 5; 10; 20;
50; 100; 200; 500; 1000
Std 2
If Std 2
Std 3
If Std 2
Note
The measuring accuracy depends on the standard solutions
selected and on the expected concentration of the ISE mea-
surement following.
2 °C from the tempera-
±
Std 1, Std 3 must be
>
Std 1, Std 3 must be
<
Operation
e
.
Std 2
>
Std 2
<
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