Thermo Orion Star, Руководство пользователя

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Thermo Electron Corporation VIII-6 Orion Star Series Meter
Dissolved Oxygen Technique
i . The highest possible accuracy is reached when calibration temperature is
the same as the measuring temperature .
ii . Moisten the sponge or absorbent cloth in the calibration sleeve with
water and insert the probe into the sleeve, but without touching the
water saturated material . For BOD measurements, this calibration can be
performed in a BOD bottle .
iii . For oxygen levels below 1 mg/L, a second zero calibration point is often
required .
b . denotes Water Calibration performed using a water sample that is
100% saturated with air . It is the least commonly used calibration method .
c . display denotes manual calibration using a water sample with a know
concentration of dissolved oxygen . It can be used to calibrate the sensor to
the value achieved by a Winkler titration .
i . A Winkler calibration involves performing a manual Winkler titration and
then using that sample as a standard . The titration oxygen level result is
entered in a Winkler calibration as the DO standard value . This correlates
the meter input to the Winkler titration . Note, this method is inherently
less accurate due to the possibility of titration errors introduced when the
calibration is set to the titration test results
d . is a zero calibration, which is used for very low level DO
measurements . Not generally required unless you are making
measurements below 5% Saturation or 0 .5 mg/L .
7 . The probe and calibration standard (water-saturated air or air-saturated water)
should be allowed to reach equilibrium before the system is calibrated .
8 . Press to accept selection and return the arrow icon to the top line .
9 . Press to return to measurement mode .