User Manual

4.2. Calibration
1.) Pour a small quantity of ph 6.86, ph 4.01 and ph 9.18 solution into
clean beakers.
2.) For a particularly accurate calibration, it is advised to use two beakers
for each buffer solution; the first is to be used for rinsing the electrode,
the second is to be used for the calibration. In this way, the risks of
contaminating the buffer solution are reduced to a minimum.
PH7
3.) Switch on the instrument.
4.) Immerse the pH electrode into a standard buffer solution with
pH = 6.86.
5.) Stir slowly the electrode in the solution until you get a stable reading.
6.) Use a small screwdriver (supplied) to adjust the calibration trimmer
(PH7) at the front of the instrument until the display shows “6.86”.
7.) Rinse the electrode with distilled water.
PH4
8.) Immerse the pH electrode into a standard buffer solution with
pH = 4.01.
9.) Stir slowly the electrode in the solution until you get a stable reading.
10.) Use a small screwdriver (supplied) to adjust the calibration trimmer
(PH4) at the front of the instrument until the display shows “4.01”.
11.) Rinse the electrode with distilled water.
PH9
12.) Immerse the pH electrode into a standard buffer solution with
pH = 9.18.
13.) Stir slowly the electrode in the solution and wait for the reading
stabilized until it displays 9.18.
14.) Rinse the electrode with distilled water.
15.) The calibration for the instrument is now complete.
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