12
6. Operation
Screw the
sensor
to the 1st tube.
6.4. Calibration
The sensor and the measuring instrument must be calibrated correctly to obtain precise measurements.
Important notes:
The sensor must be connected and polarized before calibration (see sensor manual).
During calibration, the membrane must not enter into contact with the surface of the water. The membrane
must remain dry since water droplets can affect calibration.
Fig. 5. Preparación
1
2
3
4
6.4.1.1. Preparation
1.
Unscrew the sensor protector.
2.
Add a small amount of water to the
calibrator tube.
3.
Empty the excess water by shaking
gently.
4.
Screw the calibrator tube to the sensor.
6.4.1. One-point calibration
6.4.1.2. Calibration
Follow the diagram.
One-point calibration is performed in air saturated water,
100% DO.
This is the most common type of calibration.
Note:
If calibration is not performed correctly, the membrane must
be cleaned and the electrolyte changed (see sensor manual).
The calibration is correct if an oxygen content of over 98% is
displayed when taking a measurement 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.
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