Hanna Instruments HI 98280 User Manual
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4.2 pH CALIBRATION
It is recommended to calibrate the meter often for
pH readings, especially if high accuracy is required.
When the pH calibration is selected, the display
shows two options: “Calibrate pH” and “Clear old
calibration”.
If “Calibrate pH” is selected, the user can perform a new calibration at 1, 2 or 3
points with standard buffers (pH 4.01, 6.86, 7.01, 9.18, 10.01), or a single
calibration with custom buffer.
If “Clear old calibration” is selected, all calibration data will be deleted and the
default data restored.
Notes
Notes
Notes
Notes
Notes
Old calibration data have to be deleted every time the pH sensor is
replaced and after performing a cleaning procedure.
When a 3-point calibration is performed, all the old data are overwrit-
ten, while with a 1 or 2-point procedure the meter will use for the miss-
ing points the data previously stored with the last 3-point calibration.
4.2.1 Preparation
Pour small quantities of selected buffer solutions into clean beakers. To minimize
cross contamination, use two beakers for each buffer solution: the first one for
rinsing the electrode and the second one for calibration.
4.2.2 Procedure
The current measured value is shown on the
main part of the display, while the buffer value
appears on the secondary level.
If necessary, press the
change the buffer value or insert a custom buffer.
1, 2 or 3-point calibration
• Immerse the probe into the selected buffer and stir gently. The current pH value,
the buffer value and “Not ready” are displayed.
• When the reading becomes stable and close
to the selected buffer value, the display shows
the “Ready” message.