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Operational Guide
28
Wrong Old Points Inconsistency
“WRONG OLD POINTS INCONSISTENCY” is displayed if
the new calibration differs significantly from the last
value of that probe in that buffer. In this case it may
be best to clear the previous calibration and attempt a
new calibration with fresh buffers.
To clear calibration information, press
CAL
then
press
CLR
. The “CLEAR CALIBRATION” message will
be displayed. Either press the
CFM
key and clear all
calibration information or press
CAL
to exit. The probe
may retain a single point calibration if first point was
accepted.
Once calibration information is cleared, the message
“CAL DUE” will be displayed
Clean Electrode
“CLEAN ELECTRODE” indicates poor electrode
performance (offset out of accepted window, or
slope under the accepted lower limit). Often, cleaning
the probe will improve the pH electrodes response.
See pH Electrode Conditioning and Maintenance for
details. Repeat calibration after cleaning.
Check Electrode Check Buffer
“CHECK ELECTRODE CHECK BUFFER” appears when
electrode slope exceeds the highest accepted slope
limit. You should check your probe and use fresh
buffer. Cleaning may also improve this response.
Bad Electrode
“BAD ELECTRODE” appears if the cleaning procedure
performed as a result of the above two messages is
found to be unsuccessful. In this case it is advised to
replace the probe.
Wrong Buffer Temperature
“WRONG BUFFER TEMPERATURE” appears if the
temperature of the buffer is outside the defined
buffer temperature range. The calibration buffers are
affected by temperature changes in a defined manner.
During calibration, the instrument will automatically
calibrate to the pH value corresponding to the measured temperature but
display it to the value at 25 ºC. Immediately after calibration, the buffer should
read the value of the buffer at the temperature of measurement.
Note
: Temperature limits will be reduced to actual sensor specifications.
Calibration
Messages
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