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36
CALIBRA
TION
% DO Saturation Calibration
Remove the shield from the probe and rinse the probe with purified water.
Shake any remaining solution off the probe. No droplets should remain on the DO sensor sensing surface.
Calibration at 100 % and 0 % Saturation
1. To calibrate at 100 % saturation, place a moistened sponge in the bottom of the calibration
beaker.
2. Place the calibration beaker on the probe body. Do not tighten the calibration beaker on the
probe threads.
3. Wait at least 15 minutes for the air to become saturated with water vapor. This condition
corresponds to 100 % air saturated water at the temperature of measurement.
4. Press
Start
to start the calibration.
5. The reading, temperature, calibration point and the “Not ready” message are displayed.
6. Once the reading has stabilized the countdown timer will count down until the display shows
the “Ready” message.
7. Press
Confirm
to accept the calibration point.
8. To calibrate at 0 %, fill the calibration beaker 2/3 full with
HI7040
zero oxygen solution.
9. Slowly place the sensors in the solution. Dislodge bubbles that may adhere to the sensors.
10. Screw the calibration beaker completely onto the probe body. Some solution may overflow.
11. The stability timer will count down until the display shows the “Ready”.
12. Press
Confirm
to accept the calibration point. The message “Storing” followed by “Calibration
completed” will be displayed.
13. Press
OK
to return to the calibration menu or
Measure
to return to the measurement screen.
Notes:
To save a one calibration press the ESC key after the standard is confirmed.