RADWAG MAX 60 Moisture Analyzer - Manual (Page 70)

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heating a sample (with application of a halogen filament) carried out by a
moisture analyzer, makes the measurement process very time efficient and
short. Measurement speed can be additionally increased by appropriate
adjusting moisture analyzer’s parameters depending on substances to be
tested.
Optimum temperature and drying time depend on type and size of a sample
to be tested, and anticipated measuring accuracy. Selection of drying
parameters can only be carried out on basis of test measurements.
12.2. Sampling and preparation
Features, preparation and size of a sample are very important factors
influencing the speed and accuracy of measurement process.
Means of sampling and preparation are extremely important for repeatability of
measurement results, as a sample should be a representative part of tested
substance.
Final measurement result is vastly conditioned by precise and considered
sample preparation. A sample used for analysis has to represent the total
structure of tested material. Sampling process should determine: sampling
means, sample disintegrating, particle size after disintegration, sample
uniformity and other. The sampling process should be carried out as quickly as
possible, so that a sample does not loose or absorb humidity from surrounding
area.
Applied sampling standards should match individual user needs and
requirements of tested material, its consistence and sample size.
Number of samples
Increasing number of tested samples also increases statistic measurement
certainty. Number of samples depends on uniformity of tested material , its
purity, accuracy of applied measuring method and anticipated accuracy of
obtained results.
Material mechanical disintegrating for measurements
Applied disintegrating method should be selected appropriately to tested
material. Substances that are hard and brittle (crisp) can be disintegrated by
cutting. Grinding such substances may cause their heating and thus humidity
vaporization, resulting in unreliable measurement results. Unless a substance