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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 follow instructions below.
The temperature calibration can be performed in one or two points.
It is better to perform a two points calibration.
The calibration can be performed in any 2 points that have at least 25 °C
distance between. It is
recommended that the first point be near 0 °C and the second point near 50 °C.
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.
•
Ensure the DO probe is connected to the meter.
•
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.
•
Use the
/
keys to set the calibration point values to that of the ice and water mixture,
measured by the reference thermometer.
TEMPERA
TURE CALIBRA
TION (for technical personnel only)
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