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voltage signals proportional to the measured value. The linear
scaling of the voltage signal can be freely adjusted at
0 mV output
corresponds to
and
2500 mV output corresponds to
.
NOTE:
Due to hardware restrictions, the very lower range of the
analog output around 0-3 mV shows slight non-linearities. For
precision measurements e.g. around 0% O2 it is therefore
recommended to map the zero oxygen level e.g. to 100 mV.
Example:
0 mV output corresponds to
-1 %O2
2500 mV output corresponds to
24 %O2
This will give 100 mV for 0 % O2, and 2200 mV for 21 %O2.
The second operation mode of the analog output is
Alarm if out of
range
. In this mode, the analog output can output only two
possible voltages: either 0 mV or 2500 mV (so actually it is now a
digital signal). The 0 mV are given if the measured parameter falls
within a specific range, which can be freely adjusted at
lower
alarm limit
and
upper alarm limit
. If the measured parameter gets
out of this range, the analog output will switch to 2500 mV. This
feature can be e.g.
utilized for monitoring
oxygen levels in a fish
tank. If the oxygen
levels
might
get
dangerous for the fish,
the 2500 mV of the
alarm output could
trigger some external
electronic
equipment
which e.g. rings a bell.
