Hanna Instruments HI 84502 - Manual (Page 21)

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• The (unstable measurement) symbol will be shown on the display until the reading
becomes stable.
• When the reading is stable and close to the selected buffer, the (unstable measurement)
symbol will disappear and the Confirm key will become active.
• Press Confirm to confirm the calibration.
• The calibrated value will be shown on the display and the third expected buffer value will be
automatically selected.
• After the second calibration point has been confirmed, press ESC to exit without performing
the third calibration point.
Point 3 calibration
• Remove the electrode holder with electrodes from the top of the beaker.
• Place the third beaker with calibration buffer in the beaker holder. Rinse the electrodes in a
beaker containing the third buffer rinsing solution.
• Place the electrode holder (with electrodes) on the top of the beaker and secure it by turning
clockwise and press STIR.
• If necessary press the ARROW keys in order to select a different buffer value.
• The (unstable measurement) symbol will be shown on the display until the reading
becomes stable.
• When the reading is stable and close to the selected buffer, the (unstable measurement)
symbol will disappear and the Confirm key will become active.
• Press Confirm to confirm the calibration. The instrument stores the calibration value and
returns to calibration menu, where the date and time for the pH calibration will be updated.
Notes:
• A buffer confirmed during the calibration process is removed from the list of available buffers.
• If the value measured by the instrument is not close to the selected buffer, a
“Wrong Buffer”
error message will be shown on the display.
Check if the correct buffer has been used or regenerate the pH electrodes by following the
Cleaning Procedure (see page 40). If necessary change the buffer or the electrode.