Hanna Instruments HI 9829 - Manual (Page 51)

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7.7.3 Custom Turbidity Calibration Procedure
If the user wishes to calibrate with
standard Formazin standards it is possible
using the custom point. Prepare standards based upon published international
protocols.
The first point is zero. The second point must be a standard between 10 and 30
FNU. The third point must must be a standard prepared between 100 and 500
FNU.
Pour quantities of standard solutions into clean beakers for rinse. Fill the HI
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calibration beaker with the zero standard and follow the procedure
for calibrating zero from section 7.7.2.
• After confirming zero, clean out the calibration beaker and refill with custom
point 2 FNU standard. Immerse the sensor in the Point 2 custom FNU rinse
beaker and then shake off excess solution. Place the sensor into the Point 2
custom FNU calibration beaker and take measures to eliminate bubbles from
the optical area. Press <Cal. point> and T9 key pad to display the standards
value. Press <Accept>.
• When the reading is stable the display shows the “Ready” message.
• Press <Confirm> to accept the second calibration point. The calibration can
be stopped after the 2nd Custom FNU point. Press ESC. Storring will be
displayed followed by Calibration completed. Press <OK> or <Measure>.
Alternately, continue with Custom Point 3 standard using the procedure
described above.
7.8 TEMPERATURE CALIBRATION
The probe is factory calibrated for temperature readings. The user can perform a
single point temperature calibration or restore fac-
tory calibration. This procedure requires a refer-
ence temperature measuring instrument.
• Select “Temperature” from the “Calibration”
menu.
• Select “Calibrate temperature”.
• Insert the probe in an isothermal bath with ref-
erence instrument and allow the probe to come to thermal equilibrum.
• Use the keypad to enter the known temperature and then press <Accept> to
confirm.
• The stability timer will count down and the message “Ready” and <Confirm>
will be displayed.
• Press <Confirm> to store the calibration point.