73
Dissolved Oxygen Measurement in
Carbonated Beverages
(Only with Protos 3400(X): SW3400-011)
Application-specific add-on function for breweries
Recommended only for SE 7*7 ... series sensors!
This add-on function simplifies parameter setting since all steps not required
for dissolved oxygen measurement in carbonated beverages are omitted. It
simultaneously acts on all installed OXY modules (module firmware version 2.2
and higher).
Function principle:
The following processes are automated by the additional function, i.e. all
parameters required for the respective program step are set automatically.
During the filling process, for example, it must be ensured that as little oxygen
as possible is dissolved in the beer to extent its shelf life.
During oxygen trace measurement the sensor is operated with a very low
polarization voltage (-500 mV). This results in low cross-sensitivity to CO
2
.
For a calibration in air, this polarization voltage is too low.
It must be set to -675 mV and afterwards be reduced again to -500 mV for
measuring in the trace range.
Be sure to wait long enough for the sensor to stabilize.
Opening and closing of valves causes pressure variations in the beer pipes
which momentarily falsify the O
2
signal. Therefore the input signal must be
attenuated correspondingly to suppress transient interferences.
