3.9 pH CALIBRATION - MANUAL
Select the pH menu. Entering buffer values manually can be carried out in either the pH SETUP MENU or
in CALIBRATION mode.
Calibration is performed by selecting the pH mode and then moving the cursor to the CAL menu option and
pressing .
An icon will appear indicating the CAL 1 buffer value and the first part of the calibration. The buffer value(s)
can be changed at this point by entering the CAL BUFFERS... menu and setting new values by using the
numeric keys and pressing .
To calibrate the instrument select the CALIBRATE menu option using the arrow keys. The electrode(s)
should be placed into the first buffer solution and the reading allowed 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 2 buffer value. If a one point calibration only is required select
the EXIT option using the arrow keys and pressing . The instrument will return to the pH mode.
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.
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