Hanna Instruments HI 9828, Instruction Manual, Page: 32 / 60

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4.2.2 Procedure
During calibration the current measured value is
shown on the primary display and the buffer
value on the secondary display.
By pressing the BUFFER soft key it is possible to change the buffer value or insert
a custom buffer.
One to three-point calibration
• Immerse the probe into the selected buffer and stir gently. On display the
current pH value, the buffer value and the message “Not ready” appear.
• When the reading is stable and close to the
selected buffer the display shows “Ready”.
• Press CONFIRM to accept the value or BUFFER
to select another buffer value with the arrow keys.
• After the first calibration point is confirmed, immerse the probe in the second
buffer solution and stir gently.
• When the reading is stable and close to the selected buffer the display shows
the message “Ready”.
• Press CONFIRM to accept the value or BUFFER to change the buffer value.
• After the second calibration point is confirmed, proceed as above by immers-
ing the probe in the third buffer solution, stirring gently and waiting for the mea-
sure stability.
• At the end of calibration on display the following messages appear: “Storing
data on probe, please wait...”, “Updating GLP data, please wait ...” and “Cali-
bration completed”.
• Press OK to close the last message and return to the calibration menu.
• To return to the main menu, from the calibration menu, press ESC repeatedly.
NOTE : the user can quit the pH calibration mode at any time, after 1 or 2
confirmed buffers, by pressing the ESC key.
Custom buffer calibration
HI 9828 allows a one point calibration with a custom buffer value, set by the