wtw OxiTop C, Руководство по эксплуатации

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OxiTop
®
Control OC 100 Overview
ba31114e06 06/2012
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1 Overview
1.1
The system
OxiTop
®
Control
The classical application field for the OxiTop
®
measuring heads and controller
is the BODx determination (BODx = Biochemical Oxygen Demand for the time
x). The evaluation of biological degradability (e.g. test according to OECD
301F) is also part of this field.
With different sample vessels, the OxiTop
®
-C measuring heads in conjunction
with the OxiTop
®
Controller 110 can also be used in other areas such as

Evaluation of respiration and toxicity in earth, sludge, waste and sediment
(e.g. extraction of contaminated earth according to recovery concepts)
 Evaluation of the respiration rate of cell cultures
 Microbiological growth and stress examinations
 Measurement of anaerobic degradation processes (e.g. biogas determina-
tion)
Accessories: see WTW catalog and price list
1.2 The measurement principle
The respirometric measurement is a pressure measurement. If oxygen is
consumed in a closed vessel at a constant temperature, a negative pressure
develops. If a gas is released, an overpressure develops. The OxiTop
®
-C
measuring head measures and stores this pressure for the whole duration of a
measurement once started.
The OxiTop
®
OC 100 controller collects the pressure values from the
measuring heads and processes them.
The formula shown below is the basis for all calculations for the BOD using the
values from the OxiTop
®
-C measuring head.
The interpretation of the pressure differences in the temporal course depends
on the measured material and its preparation and on the sample manipulation
(e. g. intermediate aerations) during the measuring period.
1.3 Data management
The measuring head records the measured values and stores the measuring
data. Using the controller, the collected and stored data are read out from the
measuring head and stored in the “sample management“. Starting at the
OxiTop
®
sample management, it is possible to make the graphical and statis-
tical evaluation of the sample data.
The data can be transferred from the controller to a computer via the RS232
interface. The read-out software Achat OC facilitates to process the stored data
further.