Measurement - Apera Instruments PH20 Value User Manual

■ Notes
a) The 1st point calibration must be 7.00 pH. Perform the 2nd and 3rd point calibrations (4.00 or 10.01 ) right
after the 1st point calibration is finished. Do NOT turn off the tester before you calibrate 2nd or 3rd point.
Otherwise, you will need to restart the calibration process with 7.00 pH first.
b) In calibration mode, when the measured value is not fully stabilized (
will cause Er2).
c)
Only pH 4.00 and pH 7.00 buffer solutions are included in the test kit, pH 10.01 is not. You can purchase it
separately if needed (when your target pH level is >8.0 pH).
d) Having good-quality standard calibration buffers ready is the foundation for reliable pH measurement. The
bottled buffers (2 oz.) in the kit can be used for up to 10 times of calibration (make sure they are tightly closed
when not in use). After that, we recommend replacing them with new ones to keep the accuracy.
e) Tester will automatically recognize pH buffer solution, users can choose calibration points: 1 point, 2 points, or
3 points. For details, please refer to the following table:
1-point
Calibration
2-point
Calibration
3-point
Calibration

5. Measurement

5.1. Short press
5.2. Rinse the probe in pure water. Then shake off excess water.
5.3. Fully submerge the probe into your sample solution at least 1 inch deep, then hold still. Record the readings
after the reading is fully stabilized (
■ Pure Water pH Measurement
When testing pure water like tap water, drinking water, RO water and distilled water, it will take longer for the
readings to get fully stabilized (typically 1-5 minutes). Please be patient. If still not working, add Apera 3M KCL
(AI1107) to your pure water at the ratio of 1:1000 (e.g. 1 ml KCL to 1000 ml water) to accelerate stabilization while
minimizing pH change. If the accuracy is not meeting your requirement, please contact us at info@aperainst.com to
find the specialized meter designed for pure water pH test.
Calibration Solution
7.00 pH
7.00 pH and 4.00 pH
7.00 pH and 10.01 pH
7.00 pH, 4.00 pH
and 10.01 pH
to power on the tester. Remove the probe cap.
Calibration icon
comes up and stays on screen).
is not staying on LCD), pressing
When
Required Accuracy≥ 0.3 pH
Target pH level< 8.0 pH
Target pH level> 8.0 pH
Wide measuring range
3