Hanna Instruments HI 98186 - Manual (Page 51)

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TEMPERATURE CALIBRATION TEMPERATURE CALIBRATION TEMPERATURE CALIBRATION TEMPERATURE CALIBRATION TEMPERATURE CALIBRATION
(((((for technical personnel only for technical personnel only for technical personnel only for technical personnel only for technical personnel only)))))
All the instruments are factory calibrated for temperature.
Hanna’s DO 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 instructions below.
The temperature calibration can be performed in 1 or 2 points.
It is better to perform a 2 points calibration.
The calibration can be performed in any two points that have at least 25 ºC
distance between. It is recommended that the first point be near 0 ºC and the
second point near 50 ºC.
Press CAL from any measure mode (DO, BOD, OUR or SOUR).
The calibration menu will be displayed.
Press the T functional key to select the temperature calibration.
•
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.
• Immerse the DO 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.