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6. Operation
ENGLISH
6.4.2. Two-point calibration
6.4.2.1. Preparation
1.
Unscrew the sensor protector.
2.
Dip the sensor into an oxygen-free solution.
3.
Stir the sensor gently.
6.4.2.2. Calibration
Follow the diagram.
Note:
To perform a two-point calibration, you must be certain
that the solution is oxygen-free; otherwise, one-point
calibration (100% DO) using the calibrator tube is
preferable.
If calibration is not performed correctly, the membrane
must be cleaned and the electrolyte changed (see sen-
sor manual). The calibration is correct if an oxygen
content of over 98% is displayed when taking a mea-
surement in the calibrator tube. A value of over 99%
is optimal.
If the measuring instrument is not used for 5 minutes, it
shuts off automatically.
Dip the sen-
sor into an
oxygen-free
solution
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