Thermo Orion Star, Руководство пользователя

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VIII-11
Orion Star Series Meter
Thermo Electron Corporation
Dissolved Oxygen Technique
1 . Perform either an , , or (Winkler) calibration
before continuing with the Probe Zero calibration . See the
appropriate calibration procedure above .
2 . Enable the calibration function in Setup before the
calibration is started .
3 . Prepare an oxygen scavenging solution, such as sodium
sulfide . Add 15 grams of sodium sulfide to 250 mL of
deionized water . Stir until most of the salt has dissolved .
Transfer the solution into a BOD bottle . Place the overflow
funnel into the bottle so that it is snugly sealed .
4 . Place the probe into the bottle ensuring that the thermistor
is fully submerged in the solution . Place the bottle on a
magnetic stirrer and stir gently .
5 . Allow the solution to eliminate all oxygen from the
membrane module . This should take at least 5 minutes .
6 . To initiate the Probe Zero calibration, press . The “cal”
indicator will light .
7 . While the electrode signal is stabilizing, the meter will
flash a dissolved oxygen reading (based upon the current
calibration data) in the main field . Once the input has
stabilized,
will be displayed .
8 . The user must press to zero the probe .