If a two point calibration is required the electrode(s) should be rinsed and then placed into the second buffer
solution. Allow the reading to stabilise (the endpoint symbol will be displayed) prior to pressing the key.
The display will then update to the standard buffer value, corrected for temperature (actual temperature will
be displayed).
The icon will then change to show the CAL 3 buffer value. If a two point calibration only is required select
the EXIT option by using the arrow keys and press . The instrument will then return to the pH mode.
If a three point calibration is required the electrode(s) should be rinsed and then placed into the third buffer
solution. Allow the reading to stabilise (the endpoint symbol will be displayed) prior to pressing . The
display will then update to the standard buffer value, corrected for temperature (actual temperature will be
displayed). The instrument will then return to the main pH display.
Once calibration is completed the instrument is now ready to perform sample measurement.
Rinse electrode(s) and place in sample. Allow the reading to stabilise (the endpoint symbol will be displayed).
Repeat for each sample
At the end of sample measurement re-check the calibration of the instrument using one standard solution.
3.10 ERROR CODES
If a problem is detected during calibration the following error codes will be displayed;
CAL OUT OF RANGE
This indicates that the instrument has calculated an electrode ofset at pH7 outside the -30 to +30mV limits.
The error code will be displayed for 3 seconds and will then reset the calibration back to the ideal Nernst
response (0mV @ pH 7, 59.16mV/pH @ 25°C).
SLOPE OUT OF RANGE
This indicates that the slope value is out of range. The error code will be displayed for 3 seconds and will then
reset the calibration data back to the ideal Nernst response (0mV @ pH 7, 59.16mV/pH @ 25°C).
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