GANN 30001430, Operating Instructions Manual

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Active Electrode B 50 und B 60
The active electrodes B 50 and B 60 are dielectric moisture sensor with integrated circuitry. It is
intended specifically for determining moisture absorption and moisture distribution in building
materials such as for example brickwork, concrete, screed, wood, insulating materials, etc.
The basis of measurement is the dielectric constant measurement method. Between the ball
electrode and the material to be measured with which it comes into contact, a measurement field is
set up, which is affected by the density of the building material to be measured and its moisture
content. If the density of the material is constant, changes in the capacity field can be matched to a
change in the moisture content of the material being measured.
The measuring range extends from 0 to 199 digits, i.e. the displayed values are relative values.
They indicate the distinction between dry and moist building material. The higher the measured
value, the higher the moisture content of the material being measured. Drawing conclusions about
the actual moisture content in per cent from the relative measured is only permissible in the case of
a normal drying process.
The bulk density of the building material to be measured is in this case a factor of influence which
has to be taken into account. High bulk densities lead to higher displayed values, independently of
the moisture content.
Use of active electrode B 50 and B 60
In order to avoid influencing of the measurement result by the hand of the operator, the electrode
should only be held by its lower half during checking and measurement. The upper half of the
electrode must remain free.