Hanna Instruments HI 3221 Instruction Manual page 22

The instrument will display "Calibration Cleared".
All previous calibrations, are cleared and the instrument continues in calibra-
tion mode. When new calibration points are confirmed, they are kept.
Note: If Clear calibration is invoked during the first calibration point, the
instrument returns to measurement mode with CAL DUE message flashing.
ELECTRODE CONDITION
The display is provided with an icon, and a numeric value (unless the feature
is disabled) which gives an indication of the electrode status after calibration.
The "cond" remains active until the end of the calibration day.
Note: The electrode condition is evaluated only if current calibration includes
at least two standard buffers.
CLEAN ELECTRODE WARNING
Each time pH calibration is performed, the instrument internally compares the
new calibration with the one previously stored.
When this comparison indicates a significant difference, the "Clean elec-
trode" warning message is displayed to advise the user that the pH electrode
may need to be cleaned (see ELECTRODE CONDITIONING & MAINTENANCE
section for details, page 57).
After cleaning, perform a new calibration.
Note: If the calibration data are cleared, the comparison is done with the
default values.
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