DO Calibration in % Saturation Mode
The HL103 pocket DO/temperature tester can be calibrated quickly in air. In the percentage
saturation mode, the tester is able to perform either 1 or 2 points calibration. For single point
calibration, we recommend that you perform 100% saturation calibration in the air. For the 2
points calibration, zero oxygen solution is required.
100% SATURATION CALIBRATION:
1.1 Ensure that 1 point calibration is selected in the setup menu.
1.2 Once the dissolved oxygen probe is connected with the tester, turn the meter on and wait
for 10 to 15 minutes to polarise the sensor.
1.3 Press CAL key, the tester shows “CAL1/100%”.
1.4 Hold the DO probe in the air or place the sensor into air-saturated water for 3 to 5 minutes.
Press ENTER key to start the calibration. Wait for the reading to stabilise; the display
shows “END”. The unit returns to measurement mode automatically. Single point
calibration is completed.
2 POINTS CALIBRATION:
2.1 Ensure that 2 point calibration is selected in the setup menu.
2.2 Repeat steps 1.2 to 1.4 above. When the first calibration point is complete, the display
will show “CAL2/0%”. The unit prompts you to continue with second point calibration.
2.3 Immerse the probe in the zero oxygen solution, stir the solution gently.
2.4 Press ENTER key to confirm. Wait for the reading to stabilise (this can often take more
than 10 minutes), the display shows “END”. The tester returns to measurement mode
automatically. Calibration is completed.
N.B. Performing a percentage saturation calibration will simultaneously calibrate the
corresponding mg/L (or ppm) concentration value. Therefore, additional mg/L calibration isn’t
required in most circumstances.
