Xylem WTW Oxi 3205, Operating Manual

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Oxi 3205 Operation
23 ba75797e05 12/2017
4.4.2 Measuring
You can carry out D.O. measurements as follows:
Selecting the
displayed
measured parameter
You can switch between the following displays with <M> :

D.O. concentration [mg/l]

D.O. saturation [%]

D.O. partial pressure [mbar].
Salinity correction When measuring the concentration of see water, a salinity correction is
required. When the salinity correction is switched on, the
[Sal] indicator
is displayed in the measuring window.
You can switch the salinity correction on or off and enter the salinity in
the menu for calibration and measurement settings (see section 4.4.3).
Stability control
(AutoRead )
The stability control function (AutoRead) continually checks the stability
of the measurement signal. The stability has a considerable impact on
the reproducibility of measured values. The display of the measured
parameter flashes until a stable measured value is available.
Criteria for a stable
measured value
The Stability control function checks whether the measured values are
stable within the monitored time interval.
The minimum duration until a measured value is assessed as stable is
the monitored time interval. The actual duration is mostly longer.
1 Perform the preparatory activities according to section 4.4.1.
2 Immerse the D.O. sensor in the test sample.
O
2
7.92
mg/l
25.1
°C
Measured parameter Time interval Stability in the time interval
D.O. concentration 20 seconds
Δ
: Better than 0.05 mg/l
D.O. saturation 20 seconds
Δ
: Better than 0.6 %
D.O. partial pressure 20 seconds
Δ
: Better than 1.2 mbar
Temperature 15 seconds
∆
: Better than 0.5 °C