29
CALIBRA
TION
8. Once the reading has stabilized the countdown timer will count down until the display shows the
“Ready” message. Press
Confirm
to accept the calibration point.
Note:
To save a one or two-point calibration press the ESC key after the buffer is confirmed. The
message “Storing” followed by “Calibration completed” will be displayed.
9. After the calibration point is confirmed, to avoid cross-contamination immerse the sensors in the
next calibration buffer rinse solution and stir gently.
10. Repeat the calibration procedure outlined above with the second and third buffers.
11. After the third buffer has been confirmed, the message “Storing” followed by “Calibration
completed” will be displayed. Press
OK
to return to the calibration menu or
Measure
to return
to the measurement screen.
pH Calibration Error Messages
The
HI981954
displays a series of messages if an error has occurred during calibration.
• “Input out of scale”: the pH value is out of range. The pH sensor may require replacement.
• “Check sensor”: the electrode may be broken, very dirty or the user has attempted to calibrate the
same buffer value twice.
• “Check sensor” / “Clean sensor”: the electrode is broken or very dirty.
• “Invalid temperature”: the buffer temperature is outside the acceptable range.
• “Wrong buffer”: the displayed pH reading is too far from the selected buffer value. This is often
seen immediately after a buffer calibration has been completed but before the pH sensor has been
moved to the next buffer. Check if the correct calibration buffer has been selected.
