Hanna Instruments HI 84430 User Manual

Page 20

TEMPERATURE CALIBRATION PROCEDURE

(for technical personnel only)

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 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.
• To enter user calibration screen press and hold down the ARROW keys simultaneously, then

power on the instrument. After a few seconds the User calibration screen is displayed.

• Press Temp function key to enter temperature calibration.
• Immerse the temperature 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 calibration point value to that of the ice and water measured

by the reference thermometer.

• The (unstable measurement) symbol will be shown on the display until the reading becomes

stable.

• When the reading is stable and close to the selected calibration point, the (unstable

measurement) symbol will disappear and the Confirm key will become active.

• Press Confirm to confirm the calibration point.
• The meter will be automatically move to the second calibration point, and will display 50 °C for

the buffer value.

• Immerse the temperature probe in the second vessel as near as possible to the reference

thermometer. Allow a few seconds for the probe to stabilize.

• Use the ARROW keys to set the calibration point value to that of the hot water, measured by

the reference thermometer.

• The (unstable measurement) symbol will be shown on the display until the reading becomes stable.
• When the reading is stable and close to the selected calibration point, the (unstable

measurement) symbol will disappear and the Confirm key will become active.

• Press Confirm to confirm the calibration point. The instrument will return to the pH meter/

titrator main screen.

Note: If the reading is not close to the selected calibration point, the “Wrong” message will be

displayed. Change the temperature probe and restart the calibration.

If the temperature probe is disconnected or the measured temperature is out of the - 20 to120 °C range
the instrument will display “----”. The calibration point value can be changed using the ARROW keys.