Hanna Instruments HI 222 - Manual (Page 25)

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The instruments are factory calibrated for temperature.
Hanna’s temperature probes are interchangeable and temperature calibra-
tion is not necessary when replaced.
If the temperature measurements are not accurate, temperature recalibration
should be performed.
For an accurate recalibration, contact your dealer or the nearest Hanna
Customer Service Center, or follow the instructions below.
• Switch off the instrument.
• Prepare a vessel containing ice and water and another one containing hot
water (around 50 °C). Place insulation material around the vessels to
minimize temperature changes during calibration.
• Use a ChecktempC or a calibrated thermometer with a resolution of 0.1 °C
as a reference thermometer.
• Immerse the temperature probe and the ChecktempC into the vessel
containing ice and water. Wait a few minutes for the probe to stabilize.
• Press the CAL and LOG keys simultaneously and then switch the instru-
ment on. After a few seconds, the instrument enters the temperature
calibration mode. The “CAL” tag will come on. The primary LCD will
display the measured temperature or the ”- - - -” message if the
measured temperature is out of range. The secondary LCD will display 0.0 °C
(First calibration point). The “ ”tag will blink until the reading has
stabilized.
• Use the ARROW keys to set the reading on the secondary LCD to that of
ice and water measured by ChecktempC (for example, -0.1 °C).
• When the reading is stable and close to the selected calibration point, the
“CFM” tag will blink.
• Press the CFM key to confirm the calibration or the CAL key to leave the
calibration mode.
• The secondary LCD will display 50.0 °C (Second calibration point).
• Immerse the temperature probe and the ChecktempC into the second
vessel.
• Allow a few minutes for the probe to stabilize.
CAL
C
-0.1°C
TEMPERATURE CALIBRATION
(for technical personnel only )