iQntrol DOS-MODBUS
Original manual in German Version 1.0.2 2022.10.06
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8.2.5.3
Main menu
Calibration
Redox electrode
As a rule, the IQntrol DOS MODBUS device series is delivered with the ½“ redox
electrode. Therefore, the menu on the left must be selected.
In the event that the device works with the classic redox combination electrode,
please select the menu on the right.
The Calibration
redox electrode menu enables a fine-tuning of the redox
measurement. The redox test solution supplies a voltage of 468 mV at 25 °C, see
bottle label.
Since the voltage can be chosen freely, the fine-tuning may also be done with
other redox test solutions, e.g., 220 mV or 640 mV.
When making a comparison, please note the temperature dependence of the
test solution! See label
At the end of the menu, the set deviation is shown as Offset. In case of minor
deviations, the calibration is adopted immediately.
In case of deviations larger than ± 41 mV, a cleaning notice is displayed.
In case of deviations larger than ± 61 mV, the calibration is rejected and an
exchange of the pH electrode is suggested. The controller continues to work with
the values of the most recent successful calibration.
If the exchange of the electrode does not remedy the problem, the fault may be
with the pH electrode cable or the measuring amplifier.