Hanna Instruments HI 9828 - Manual (Page 33)

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4.3 DISSOLVED OXYGEN CALIBRATION
If D.O.% saturation range is calibrated, D.O. concentration range will also be
calibrated, and vice-versa.
The D.O.% saturation value is referred to the D.O. concentration in air (100%).
For this reason it is recommended to calibrate the probe near the area where the
measurements will be taken.
Also note that the D.O. concentration values are based on D.O.% saturation,
temperature, salinity and atmospheric pressure. It is recommended to use a stan-
dard solution or a reference D.O. meter to compare readings during calibration.
The calibration of D.O.% saturation range can be performed at 1 or 2 standard
points (0% and 100%), or at a single custom point (50 to 500%).
The calibration of D.O. concentration range can be performed at a single cus-
tom point (4 to 50 mg/L).
4.3.1 Procedure
Choose the D.O. calibration mode in the main
calibration menu, then select the calibration type
using the arrow keys and confirm by pressing OK.
D.O. % saturation
This calibration starts by default with 100 %.
• Fill the calibration beaker with approximately 4
mm (5/32”) of distilled water and screw it on
the probe.
• The message NOT READY is displayed until a
stable reading is reached.
• To change the standard calibration point, press
the CAL. POINT softkey and select the desired
standard point.
• To insert a different calibration value, press CAL.
POINT and then CUSTOM. Insert the desired
value using the keyboard.
• When the reading is stable, READY and CONFIRM appear. Press CONFIRM to
store the calibration point.
• After the first calibration point is confirmed, put the probe in a zero oxygen
standard solution and wait for stable reading.