Hanna Instruments HI 4211 - Manual (Page 40)

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Three buffer entry types are available: Automatic, Semiautomatic and Manual Selection. The default option is
Manual Selection.
To calibrate the instrument using Manual Selection buffer entry type:
• Press
. If the instrument was calibrated before and calibration was not cleared, the old calibration
can be cleared by pressing . After 10 seconds, will no longer be available.
Note: It is very important to clear calibration history when a new electrode is used
because most errors and warning messages that appear during calibration
depend on calibration history.
• Immerse the pH electrode and the temperature probe approximately 4 cm
(1½”) into a buffer solution of your choice (pH 1.68, 3.00, 4.01, 6.86, 7.01,
9.18, 10.01, 12.45 or a custom buffer) and stir gently. The temperature probe
should be close to the pH electrode.
• Select the used pH calibration buffer with or . The “Please
wait...” message will appear on the LCD until the reading is stable or the buffer
is validated.
• If the pH buffer is validated, will appear on the LCD. Press to update calibration. The
calibration buffer will be added to the Calibrated Buffers section.
• Immerse the pH electrode and the temperature probe into the next buffer solution and follow the above
procedure or press to exit calibration.
Notes: • The new added calibration point will replace an old one
if the difference between them is ±0.2 pH.
• If the existing stored calibration is full (five calibration
points), a pop-up menu will be displayed on the LCD
in which you can select with
or
keys the buffer you want to replace with the current
buffer. Press
to delete the selected buffer
and then press to update calibration with
the new buffer.
• When in MTC mode, if pressing after entering
pH calibration and while a HANNA pH calibration buffer
with a x.xxx resolution is selected, a pop-up menu will
be displayed on the LCD in which the temperature value
can be ajusted using
or . Press
to save the new temperature value.