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6 pH Calibration
6.1 Calibration Steps
1) Short press
to turn on the meter; rinse the probe in distilled water, shake the meter in the
air and use tissue paper to dap off excess water
(never rub or wipe the sensor tip)
.
2) Pour certain amount of pH 7.00 and pH 4.00 buffer solution into the corresponding calibration
bottles (to about half volume of the bottle);
3)
Long press
to enter calibration mode; Short press
to exit.
4)
Place the probe in pH7.00 buffer solution, shake it for a few seconds, and allow it to stand still in
the buffer solution until a stable reading is reached. When stable icon
stays on the LCD
screen, short press
to complete 1
st
point calibration and the tester returns to measurement
mode. Indication Icon
will appear at the bottom left of the LCD screen.
5)
Rinse the probe in distilled water and dry it. Long press
to enter calibration mode to perform
2
nd
point of calibration.
6)
Place the probe in pH 4.00 buffer solution, shake it for a few seconds, and allow it to stand still
in the buffer solution. When stable icon
stays on the LCD screen, short press
to
complete 2-point calibration and the tester returns to measurement mode. Indication icon
will appear at the bottom left of the LCD screen.
7) If necessary, rinse the probe in distilled water and dry it, and place the probe in 10.01 buffer
solution (sold separately) to complete 3
rd
point of calibration according to the steps in 6),
will appear at the bottom left of the LCD.
6.2 Notes
1) Tester will automatically recognize pH buffer solution. Users can perform one-point, two-point,
or three-point calibration.
For the 1
st
point calibration, only 7.00 pH/6.86 pH solution can be
used
. Then use other buffer solutions to conduct 2nd or 3rd point calibration.
Perform the 2
nd
point calibration (4.00 pH) immediately after the 1
st
point.
Do NOT turn off the meter before
you perform 2
nd
point calibration. If the meter is turned off after 1
st
point calibration, users will
need to restart the calibration process with the 7.00 pH or 6.86 pH first and the 2
nd
point
following after. Otherwise, Er1 will occur.
2) The
tester will automatically recognize 5 kinds of pH buffer solutions in both USA and NIST
series of standards. Refer to the table below:
Calibration
USA Series
NIST Series
Calibration
Indication Icon
Recommended
Accuracy and
Range
1-point
1) 7.00 pH
1) 6.86 pH
Accuracy ≥ 0.1
pH
2-point
1) 7.00 pH
2) 4.00 or 1.68 pH
1) 6.86 pH,
2) 4.01 pH or 1.68
pH
Measurement
Range
<
7.00 pH
1) 7.00 pH
2) 10.01 or 12.45
pH
1) 6.86 pH,
2) 9.18 pH or 12.45
pH
Measurement
Range
>
7.00pH
3-point
1) 7.00 pH
2) 4.00 or 1.68 pH
3) 10.01 or 12.45
pH
1) 6.86pH
2) 4.01 or 1.68pH,
3) 9.18 pH or 12.45
pH
Wide
Measurement
Range