Hanna Instruments HI 3512 - Manual (Page 23)

23
Wrong slope
The calibration cannot be confirmed.
The evaluated slope is less than the lowest accepted value (80% of
default slope).
The evaluated slope is more than the highest accepted value (110 % of
default slope).
Wrong buffer
The calibration cannot be confirmed.
The pH reading is not close to the selected buffer. Select another buffer
using the
ARROW keys or change the buffer.
“ Electrode Dirty/Broken“ alternatively with “Buffer Contaminated“.
The calibration cannot be confirmed.
The offset of the electrode is not in the accepted range. Check if the
electrode is broken or clean it following the CLEANING PROCEDURE (see
page 74). Check the quality of the buffer. If necessary, change the
buffer.