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11. CALIBRATION
It is not necessary to calibrate the combination meter before each measurement. It is
recommended to perform a calibration before every tenth measurement or every two
weeks. If the enclosed buffer/calibration solutions are used up, you can purchase more
as an accessory.
a) Measuring probe for the ph-value
• Insert the measuring probe into the combination meter if you have not done so yet. Switch
on the combination meter The operating mode “PH” must be displayed now.
• Carefully rinse the tip of the measuring probe with distilled water to remove the liquid residue
of the preceding measurements. Wipe the measuring probe dry.
• Put the measuring probe into the buffer solution with pH value 7, so that the tip of the
measuring probe submerses by about 2 - 3 cm. Move the tip of the measuring probe back
and forth in the buffer solution a bit.
Wait for at least 30 seconds until the display of the measured value in the display stabilises a
little.
• Keep the button “ /CAL” (5) pushed (approx. 3 seconds), until “CAL” (C) appears at the
bottom of the display and the value “7.00” flashes in the display (or a value according to the
liquid temperature; see print on the buffer solution).
Calibration starts now.
A brief push of the button “ /CAL” (5) interrupts calibration prematurely.
• When calibration is completed, the display shows “SA” (“Save”) and then “End”; then the
display shows the measured pH value.
• Pull the measuring probe from the buffer solution. Rinse the tip of the measuring probe with
distilled water and wipe it dry.
• Put the measuring probe into the buffer solution with pH value 4, so that the tip of the
measuring probe submerses by about 2 - 3 cm. Move the tip of the measuring probe back
and forth in the buffer solution a bit.
Wait for at least 30 seconds until the display of the measured value in the display stabilises a
little.