Hanna Instruments HI931, User Manual, Page: 110 / 218

7-12
pH MODE
•
In ATC mode, the pH value for custom buffers can be modified by pressing .
•
If the Automatic Buffer entry type was selected for the calibration procedure, the titrator will automatically select the closest
buffer to the measured pH value from the buffer group.
•
If the Semiautomatic Buffer entry type was selected use the or to select the buffer. Only buffers in the
buffer group will be displayed.
CALIBRATION MESSAGES:
• Wrong Buffer. Please check the buffer: This message appears when the difference between the pH reading and the value of
the selected calibration buffer is significant. If the message is displayed, check if you have selected the appropriate calibration
buffer.
• Wrong buffer temperature: This message appears if the buffer temperature is out of the defined temperature range.
• Clean the electrode or check the buffer. Press to update calibration: This message alerts the user that some dirt
or deposits could be on the electrode, or the buffer is contaminated.
• Slope too low. Please check the buffer: This message appears if the current slope is under 80% of the default slope.
Recalibrate the instrument using fresh buffers.
• Slope too high. Press to clear the old calibration: This message appears as a result of an erroneous slope
condition.
7.4. LOGGING
Data logging is available in pH mode. It can be logging on demand (Manual Logging) or automatically (Interval Logging) at
predefined time intervals.
To customize the logging report:
• Press
to display the Data Parameters screen.
• Highlight the
Setup pH/mV/ISE
Report option and press to display the
Setup pH/mV/ISE
Report screen.
• Use the and keys to highlight the data field that you want to show/hide in the pH/mV/ISE report and then press
to activate/deactivate it.
• Each field marked by “*” is an active field selected for the report.
• Press
to save the customized report.