INW - TempHion Instruction Manual
21
Preparing
• Select a standard that you will be using for calibration.
• Place 100 mL of distilled water in a beaker.
Note: Temperature of the water must remain the same throughout the
calibration. Temperature of the sensor must also be this temperature prior
to calibration.
One-Point Calibration
— Computing Calibration Value—
• Rinse sensor with distilled water and pat dry.
• Place sensor in beaker of distilled water, as prepared above. (Solution must
be deep enough to cover the element cutout.)
• Add 1 cc of selected standard to the water. Depending on which solution you
are using, this will result in a concentration as shown below:
• 0.1 Molar NaBr (Bromide)
=
79.10 ppm
• 0.1 Molar NaCl (Chloride)
=
35.15 ppm
• 100 ppm (Chloride)
=
0.99 ppm
• 1000 ppm (Chloride)
=
9.90 ppm
• Stir to distribute standard evenly.
• Allow time for sensor to stabilize (15 - 20 minutes).
• In
the
Ref ppm
box for the fi rst point, enter the concentration you have chosen.
• Click
the
fi rst
Measure
button. (Readings will be in mV).
• When readings have stabilized to your satisfaction, click the
OK
button on the
pop-up box.
— Applying Calibration Values—
• Observe
the
I
value in the right hand section of the calculator. For Chloride,
I
should be between 120 and 160.
• Click
the
Apply
button to apply calibration values.
• The reference value, the computed I, and the sample temperature will be
transferred to the calibration fi elds.
• Click
OK
to save the values to the sensor.
— Verifying Calibration Values—
• Using the Real Time Monitor, take a few readings while the sensor is still in the
standard. Be sure units are set to ppm. Readings should be very close to your
selected concentration.
Two-Point Calibration
— First Calibration Point—
• Rinse sensor with distilled water and pat dry.
• Place sensor in beaker of distilled water, as prepared above. (Solution must be
deep enough to cover the element cutout.)
• Add 1 cc of selected standard to the water. Depending on which solution you
are using, this will result in a concentration as shown below: