Thermo Orion Star, Руководство пользователя

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Thermo Electron Corporation VIII-8 Orion Star Series Meter
Dissolved Oxygen Technique
Water Calibration
The calibration function must be enabled in Setup before
the calibration is started . When stability is reached, the water
standard is set to 100 % or the corresponding concentration
value .
The highest possible accuracy is reached when calibration
temperature is the same as the measuring temperature .
1 . Prepare the calibration standard by bubbling air through
a beaker of stirred deionized water for at least one hour .
Ensure that the stirring is vigorous enough to provide
adequate mixing yet not forceful enough to create a vortex
in the beaker . Make sure that the water level is high enough
to fully submerge the probe thermistors, which are located
inside the metal band above the membrane cap . Ensure that
no air bubbles accumulate on the surface of the membrane .
Note:
Some magnetic stirrers generate enough heat to change
solution temperature. To avoid this, place a piece of cardboard,
foam rubber or other insulating material between the stir plate
and sample beaker.
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2 . Place the dissolved oxygen probe into the aerated water so
that the sensors are immersed . Ensure that there are no air
bubbles accumulating on the membrane .
3 . To initiate the Water calibration, press . The “cal”
indicator will light up .