wtw inoLab Oxi Level 2, Руководство по эксплуатации

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Operation
103
4.3 Calibrating
Why calibrate? 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.
When to calibrate?
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.
You can choose between 3 calibration procedures:
AutoCal TEC is specially adapted to the WTW technical buffer solutions
as a fully automatic two-point calibration. The buffer
solutions are automatically recognized by the instrument.
AutoCal DIN is specially adapted to permanently programmed buffer
solutions according to DIN 19266 as a fully automatic
two-point calibration. The buffer solutions are automatically
recognized by the instrument.
ConCal is the conventional two-point calibration with 2 freely
selectable buffer solutions or single-point calibration as the
rapid method.
AutoRead In calibration using AutoCal TEC and AutoCal DIN, the
AutoRead function is automatically activated. The current
AutoRead measurement (with acceptance of the current
value) can be terminated at any time by pressing
g
.