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If your sample is kept at a constant temperature,
then the automatic temperature compensation
can be deactivated by selecting Fixed. Now you
must enter the fixed temperature of your sample
used for the temperature compensation of the
oxygen measurement.
6.2.5
Salinity
The salinity of the sample only has to be
adjusted for measurements in saline samples
(e.g. seawater) using an oxygen concentration
unit, like µmol/L or mg/L.
6.3
Calibration Menu
After adjusting the sensor Settings (see chapter
6.2) and the local date and time in the Options
menu (see Adjust Time and Date in chapter
6.4.1), the connected oxygen sensor needs to be
calibrated before the measurements. Note, that
the top screen of the Live Mode shows the warning Not Calibrated
after a new Sensor Code has been entered. The calibration is
performed in the Calibration menu.
The oxygen sensor can be calibrated at two
calibration points:
(1) at ambient air or in air saturated water
(Calibrate Air), and
(2) at 0%O2, i.e. anoxic conditions (Calibrate
o%). For highest precision it is recommended to calibrate both
calibration points. However, if the expected measuring range is
close to one of the calibration points, then a 1-point calibration
might be sufficient. For example if the expected measuring range
in a liquid sample is 90-100% air sat., then a 1-point calibration at
air saturated water is for many applications sufficient. In this case
