4. Preparation
4.1 Preparation of sample
You should always prepare only one sample for measurement to avoid that it loses
moisture to the environment or absorbs air humidity. In case several samples have
to be taken at the same time, they should be put into airtight containers to make sure
their characteristics do not change when stored.
Spread the sample on the sample pan evenly and in a thin layer to get reproducible results.
Uneven application of the sample causes inhomogeneous heat distribution in the
sample to be dried. This means that the sample is dried incompletely or that the drying
time is increased. Due to piling material, the upper layers will heat up more strongly,
which will cause combustion or incrustation. An excessively high thickness of the layer
or possible incrustations prevents the moisture from leaving the sample. The residual
moisture makes the measurement results non-verifiable and non-reproducible.
4.2 Tools for sample preparation
The tools and instruments used for sample preparation have a huge effect on the
accuracy and reliability of the measurement. You should avoid tools with heat-
conducting properties, i. e. which are able to transfer heat to the sample. Improper
handling and preparation of the sample will falsify the end result of the measurement.
4.3 Disposable aluminium sample pan
To be able to measure the moisture content of the sample, the sample should be
spread on the sample pan evenly and then be placed in the drying chamber of the
moisture balance. Re-using a sample pan can falsify the end result of the
measurement because of the adhering residues.
4.4 Spreading of the sample
ATTENTION:
The samples should not exceed a thickness of 8 mm and a diameter of 90 mm.
If the max. height of the sample is exceeded, this can lead to combustion or
incrustation of the sample.
The sample should be spread on the sample pan evenly, ideally in layers of 2 … 5
mm.
Make sure that the temperature probe, which is located in the cover of the moisture
balance, does not touch the sample as this will falsify the result.
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