Calibrating - Inolab pH level 2 Instruction Manual

Why calibrate?
When to calibrate?
Calibration points
AutoCal TEC
AutoCal DIN
ConCal
4.3

Calibrating

pH electrodes age. This changes the asymmetry (zero
point) and slope of the pH electrode. As a result, an inexact
measured value is displayed. Calibration determines the
current values of the asymmetry and slope of the electrode
and they are stored in the instrument.
Thus, you should calibrate at regular intervals.
l
After connecting another electrode
l When the sensor symbol flashes:
– after expiry of the calibration interval
– after a voltage interruption, e.g. battery change
Calibration can be performed using one, two or three buffer
solutions (single point calibration, two-point calibration and
three-point calibration). In three-point calibration, two sepa-
rate asymmetry and slope values (ASY1/S1 and ASY2/S2)
are determined for the two ranges between the three buff-
ers. For measuring, the calibration values relevant for the
respective range are used.
You can choose between 3 calibration procedures:
is specially adapted to the WTW technical buffer solutions
as a fully automatic two or three-point calibration. The buffer
solutions are automatically recognized by the instrument.
is specially adapted to permanently programmed buffer
solutions according to DIN 19266 as a fully automatic two or
three-point calibration. The buffer solutions are automati-
cally recognized by the instrument.
is the conventional two-point calibration with 2 freely select-
able buffer solutions or single-point calibration as the rapid
method.
Operation
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