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5. The measuring process
5.1 Preparing Measurement
Connect the sensor plug of the aw sensor to the basic device. Now the switched on
device shows the current temperature and activity of water value.
Fill the plastic container with material at least two thirds full (~50-60g). In
case of coarse, lumpy material the container should be filled at least half-way
so that the moisture conditioning can be guaranteed.
The higher the filling,
the faster the conditioning. A too low material quantity may cause a deviation of the
measuring result.
The material to measure must not come into contact with the metal protective
grid (the red line on the picture below is the absolute maximum level)
The material must not enter the inside of the grid!!
After the filling, close the measuring chamber tightly.
The right measuring value can be read off when the displayed value does not
change any more over a longer period.
(Experience value for adjustment time: Change of aw value from 0.4 to 0.6 within 10
minutes).
With unpeeled materials such as nuts it may take longer until the sample releases
moisture in its surroundings for the measurement (see AW3).
For a rapid conditioning (see AW3), the water activity measuring chamber is
equipped with a ventilator. If the humimeter AW1 basic device is switched off, the
conditioning time is extended. In case of using the automatic datalog with a
datalog time of more than 30 seconds, the device switches off
automatically between the measurements.
The filled and closed measuring chamber must not be turned over. Otherwise
the measuring sensor positioned in the cap may be polluted by the sample
material, which leads to wrong measuring results
.
Do not fill above this line
