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• Pour a small quantity of the standard solution into a clean beaker. If possible, use plastic beakers to
minimize any EMC interferences.
• For accurate calibration and to minimize cross-contamination, use two beakers for each standard solution.
One for rinsing the probe and one for calibration.
• Insert the probe in the rinse beaker.
• Swirl probe in this solution. Raise and lower 3 times to fill cell with solution.
• Insert the probe in the second beaker.
• Swirl and tap probe to remove air bubbles. Raise and lower 3 times to ensure representative sample.
• Enter calibration mode by pressing
.
• Wait to stabilize.
• If automatic standard recognition was selected in Setup, a calibration point will be automatically
displayed from the Hanna standard list (84 µS/cm, 1413 µS/cm, 5.0 mS/cm, 12.88 mS/cm, 80.0 mS/
cm, 111.8 mS/cm). The user can also select another standard value by using
and
.
• If User Standard was selected in Setup, a pop-up will prompt for the custom standard value.
• Press
to finish the calibration or
to abort calibration.
• The probe should be rinsed in deionized water.
• Shake off excess water.
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 over a larger measurement
range.
• Select the multi point calibration (see
Conductivity Setup
→
Calibration
).
• Repeat the steps from the single point calibration for each
measurement range. 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). Using a known cell constant is another way to calibrate the meter/probe
system.
Note:
When a cell constant value is used, the solution calibration will be cleared. A solution calibration can
still be made after entering a cell constant value.
CONDUCTIVITY CALIBRATION
For optimum measurements:
• Insert probe in the center of the beaker away from container bottom or walls.
• Fix the probe so it does not move during measurements and add sufficient solution to cover top vent holes
on probe.
• Gently stir solution and wait for probe to reach thermal equilibrum and verify no bubbles are entrapped
within probe electrodes.
It is recommended to calibrate the instrument frequently, especially if high accuracy is required.
The conductivity range should be recalibrated:
• Whenever the conductivity probe is replaced.
• At least once a week.
• Before USP measurements.
• After testing aggressive chemicals.
• When calibration reminder is activated (“
Conductivity Cal Expired
”).
• If the readings are far from the calibration point.
Note:
TDS, Resistivity and Natural Sea Water and Practical Sea Water Salinity readings are automatically
derived from the conductivity readings so conductivity calibration is required.
OFFSET CALIBRATION
The meter allows the user to calibrate the probe for an offset.
• Select Channel 2 and press
and then press
.
• Select the automatic standard recognition (see
Conductivity Setup
→
Calibration
).
• Leave the dry probe in the air (infinite resistance).
• Enter in calibration mode by pressing
.
• Clear any previous calibrations by pressing
.
• Wait to stabilize. The 0.000 µS/cm calibration point will appear on the screen.
• Press
to finish the probe offset calibration.
• Press
to exit calibration mode or continue calibration in the other standard solutions.
Note:
The offset calibration can be performed only if it is performed first (no other calibration points
present). Clear the old calibration if it is present.
CELL CONSTANT CALIBRATION (in solution)
Single-Point Calibration
• Select the single point calibration (see
Conductivity Setup
→
Calibration
).
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