Temperature Calibration (For Technical Personnel Only) - Hanna Instruments HI2400 Instruction Manual

TEMPERATURE CALIBRATION
(for technical personnel only)
Each meter has been factory calibrated for temperature with the supplied
DO probe and is ready for measurements.
The DO probes are interchangeable and no temperature calibration is
needed.
If the temperature measurements are not accurate, temperature recali‑
bration should be performed.
For an accurate recalibration, contact your local Hanna Instruments Office,
or follow the procedure below.
• Prepare a vessel containing ice and water and another one containing
hot water (at a temperature of around 50 °C). 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 HI76407/2 DO probe to the
appropriate socket.
• With the instrument off, press and hold down CFM&SETUP, then
power on the instrument. The "CAL" tag will appear and the sec‑
ondary LCD will show "0.0 °C".
• Submerse the DO probe in the vessel with ice
and water as near as possible to the reference
thermometer. Allow a few seconds for the
probe to stabilize.
• Use the ARROW keys to set the reading on
the secondary LCD to that of ice and water,
measured by reference thermometer. When
the reading is stable, the "CFM" tag starts
blinking.
• Press CFM to confirm. The secondary LCD will
show "50.0 °C".
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