Hanna Instruments HI 98402, Instruction Manual, Page: 10 / 20

10
TWO-POINT CALIBRATION
• Press CAL . The instrument will dis-
play the measured Fluoride
concentration on the primary LCD,
if a previous calibration exists, or
“
10.0 ” standard on the secondary
LCD, together with “ CAL ” and “ Cal
Point 1 ” tags.
• If necessary, press the STD key to select a different standard value.
• If the STD key is pressed, the instrument circles through all
available calibration standards. Choose the point corresponding to
the first calibration solution.
• The “ ” tag will blink on the LCD until the reading is stable.
• When the reading is stable and close to the selected standard,
“ CFM ” tag blinks.
• Press CFM to confirm calibration.
• The calibrated value is then dis-
played on the primary LCD and
the secondary LCD will display the
second expected standard value,
together with “
CAL
” and “
Cal
Point 2
” tags.
• After the first calibration point is
confirmed, submerse the Fluoride,
the reference electrodes, and the temperature probe approximately
3 cm (1¼”) into the second standard solution and stir gently. The
temperature probe should be close to the pH electrode.
• If necessary, press the STD key to select the appropriate buffer value.
• The “ ” tag will blink on the LCD until the reading is stable.
• When the reading is stable and close to the selected buffer,
“ CFM ” tag blinks.
• Press CFM to confirm calibration.
• The instrument stores the calibra-
tion values and returns to normal
measurement mode.
ONE-POINT CALIBRATION
• Proceed as described in TWO-POINT CALIBRATION section.
• Press
CAL after the first calibration
point was confirmed. The instruments
will memorize the one-point calibra-
tion data and will return to
measurement mode.