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All the instruments are factory calibrated for temperature.
Hanna’s temperature probes are interchangeable and no temperature
calibration is needed when they are replaced.
If the temperature measurements are inaccurate, temperature recalibration
should be performed.
For an accurate recalibration, contact your dealer or the nearest Hanna
Customer Service Center, or follow the instructions below.
• Prepare a vessel containing ice and water and another one containing
hot water (at approximately 50 °C or 122 °F). Place insulation
material around the vessels to minimize temperature changes.
• Use a calibrated thermometer with a resolution of 0.1 °C as a reference
thermometer. Connect the DO probe to the appropriate socket.
• With the instrument off, press and hold down the
Range
& keys,
then power on the instrument. The “
CALIBRATION
” tag will
appear and the secondary LCD will show “
0.0 °C
”. The primary LCD
will display the measured temperature or the ”
----
” message, if the
measured temperature is out of range.
• Immerse the temperature probe into the vessel with ice and water as
close as possible to the reference thermometer. Allow a few seconds for
the probe to stabilize.
• Use the
pq
keys to set the reading on the secondary LCD to that
of ice and water, measured by the reference thermometer. When the
reading is stable and close to the selected calibration point, “
CFM
”
tag will blink.
• Press
CFM
to confirm. The secondary LCD will
display “
50.0 °C
”.
• Immerse the temperature probe into the second vessel as close as
possible to the reference thermometer. Allow a few seconds for the
probe to stabilize.
• Use the
pq
keys to set the reading on the secondary LCD to that
of the hot water.
• When the reading is stable and close to the selected calibration
point, “
CFM
” tag will blink.
• Press
CFM
to confirm. The instrument returns
to measurement mode.
Note:
If the reading is not close to the selected calibration point,
“
WRONG
” tag will blink. Change the temperature probe and
restart calibration.
TEMPERATURE CALIBRATION
(for technical personnel only)
