Hanna Instruments HI 3221 Instruction Manual page 20

Wrong old slope
An inconsistency between new and previous (old) calibration is detected. Clear
old calibration parameters and initiate calibration from the current point. The
instrument will keep all confirmed values during current calibration.
Note: For single-point calibration the electrode condition is not displayed in
the measurement screen.
Each time a buffer is confirmed, the new calibration parameters replace the
older calibration parameters of the corresponding buffer.
If an additional single buffer calibration is added at a latter time, the new
buffer point will be added to the stored calibration.
If the existing stored calibration is full (five calibration points), after confirming
the calibration point, the instrument will ask which buffer will be replaced by
current buffer. On the Buffer line will be displayed the proposed buffer.
Press ARROW keys to select another buffer to be replaced.
Press Confirm to confirm the buffer that will be replaced.
Press CAL or ESC to exit mode. In this case, the buffer will not be entered.
Note: The replaced buffer is not removed from calibration list and it can be
selected for the next calibration points.
WORKING WITH CUSTOM BUFFERS
If at least one custom buffer was set in SETUP menu, it can be selected for calibration
by pressing the ARROW keys. The Custom function key will be displayed.
Press Custom if you want to adjust the buffer to its value at the current
temperature.
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