Hanna Instruments HI 4521 - Manual (Page 31)

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To set the Stability Criteria:
• Use or to select the Stability Criteria option.
• Press and use or to highlight the
desired option.
• Press to confirm your selection or press to
cancel operation.
Reading Mode
This option allows the user to select between
Direct and Direct / AutoHold
pH reading mode. If choosing the second option, the current reading can be frozen on the LCD when is
pressed and if the stability criterion is reached.
To set the Reading Mode:
• Use or to select the Reading Mode option.
• Press and use or to highlight the
desired option.
• Press to confirm your selection or press to
cancel operation.
Log
This option allows the user to edit the logging settings:
Logging Type, Logging Data Configuration, Sampling Period
and New Lot.
Logging Type
Three logging types are available:
Automatic, Manual and AutoHold. With the Automatic type the values are
logged automatically at constant time intervals while with the Manual type the user has the capability to log a
measured value by pressing
. With the AutoHold type the stored values are only the ones frozen on the LCD
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• Insert and rinse the probe in the first beaker in order to decontaminate it;
• Insert the probe in the second beaker;
• Tap the probe repeatedly to remove any air bubbles that may be trapped inside the sleeve.
• Enter in calibration mode by pressing ;
• Wait to stabilize;
• When the automatic standard recognition is selected, the calibration point will be automatically selected
from the Hanna standard list (84 µS, 1413 µS, 5.0 mS,12.88 mS, 80.0 mS, 111.8 mS). The user can
also select the desired standard value by using
and ;
• Otherwise (user standard), the pop-up will prompt for the custom standard value.
• Press to finish the calibration or to abort calibration.
Note: The calculated cell constant will be used for the whole range.
Multi Point Calibration
• Up to 4 calibration points can be performed in order to
increase the measurement accuracy on the wide range;
• Select the multi point calibration (see Conductivity Setup ->
Calibration);
• Repeat the steps from the single point calibration for each
calibration point. The meter will calculate a cell constant
corresponding to each calibration point;
• Press to exit calibration mode.
Note: For each range the corresponding cell constant will be displayed.
CELL CONSTANT CALIBRATION (edited by the user)
• A known value of the probe cell constant can be set by the user for the whole range (see Conductivity
Setup -> Cell Constant section)
Note: When the user cell constant is used the old calibration (in solution) will be cleared.