wtw OxiTop IS 12, Operating Manual

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Application range / Delivery equipment Instruction manual
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Recommended range of application
OxiTop

measuring systems with inductive stirring system, for respirometric
determination of the biochemical oxygen demand (BOD) according to the self-checking
method.
Delivery equipment
Model
OxiTop

IS 6 OxiTop

IS 12
Order Nr.
208 210 208 211
Inductive stirring system
(Stirring device)
6 OxiTop

instruments
12 OxiTop

instruments
Equipment
3 OxiTop

yellow
3 OxiTop

green
6 OxiTop

yellow
3 OxiTop

green
Accessories:
Accessory set 1
(brown sample bottle,
stirring rods, rubber
quivers)
6 x 12 x
Accessory set 2
(stirring rod remover,
overflow measuring
beaker 164 ml and
432 ml, sodium
hydroxide tablets,
note block)
1 x 1 x
Operation of the Single Measuring System
OxiTop

Measuring principle
BOD measurement with the OxiTop

measuring system is based on pressure
measurement (difference measurement). The measuring is made by pressure
measurement via
piezoresistive electronic pressure sensors .
With the following functions, the OxiTop

measuring system minimizes the measuring
work and is especially suited to the courses of the respirometric BOD measurement:
•
AUTO TEMP function:
Control of the temperature adjustment and automatic start of the measurement
(1 hour after starting the OxiTop

measuring system at the earliest, after 3 hours at
the latest). It is not necessary to temper the samples to exactly 20°C before starting
OxiTop

. Samples between 15°C and 20°C can be started immediately as BOD
measurement will not begin until a stable 20°C is reached. This is controlled by
the "AutoTemp" feature.
•
Data logging
Automatic measurement with daily storage of measured value for 5 days:
facilitates measurement without supervising, e. g. over the weekend.
•
Current value
Indication of measured value (0 - 40 digits) corresponds to the digits of the
previous WTW BOD instruments. Conversion of mbar to digits is stored in the
instrument, i. e. evaluation of the measured values remains unchanged.
•
Measuring range reserve
from 40 to 50 digits - for overranging without reset by opening the bottle.