wtw 208210, Инструкция по эксплуатации

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Measurement
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Measurement
Information : To measure the sample volume, usually overflow measuring
beakers or measuring cylinders are used.
Chose the volume according to the measured value expected.
Too large measuring ranges will lead to inaccurate results. To
estimate the measured value you can reckon with approx. 80%
of the CBS value.
•
Sample preparation and filling of the measuring bottles compare following
instruction: DIN 38409 part 52: "Measurement of the oxygen consumption" as
well as WTW applicationsreports see chapter "Sample preparation and
measurement"
.
•
Rinse measuring bottle with sample . Empty thoroughly.
•
Exactly measure the required oxygen-saturated (thoroughly homogenized)
quantity of the sample according to information.
•
Put the magnetic stirring rod into the bottle.
•
Insert a rubber quiver in the neck of the bottle.
•
Put 2 sodium hydroxide tablets into the rubber quiver with a tweezers .
(Caution: The tablets must never come into the sample!)
•
Screw OxiTop

directly on sample bottle (tightly close).
Start measurement:
Press S and M simutaneously.
( 2 seconds) untill the display
shows 00.
Display: Stored values are deleted.
•
Keep the measuring bottle with the OxiTop put on for 5 days at 20°C (e.g. in an
incubator). After the meas. temperature has been reached (after 1 hour at the
earliest, after 3 hours at the latest;
AutoTemp function ), the OxiTop
automatically starts the measurement of the oxygen consumption .
•
During the 5 days the sample is continuously stirred. The OxiTop automatically
stores one value every 24 hours for 5 days. To have the current value shown
press the M key.
Display current measured value:
Press M until measured value is displayed (1 second).
•
R eadout of the stored values after the 5 days have passed.