RADWAG MA 200.3Y Moisture Analyzer - Manual (Page 69)

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Obtaining short measurement time is feasible in case of small sample mass,
but sample mass cannot be too small, as it may negatively influence required
measurement accuracy.
17.2.2. Influence of sample mass on measurement result repeatability
Sample mass has considerable influence on repeatability of measurement
results obtained on a moisture analyzer. Relation between sample mass and
repeatability is presented in below table.
Sample mass Repeatability
to 2g ± 0,24%
to 10g ± 0,06%
Over 10g ± 0,04%
Data provided in the above table refer to an ideal and uniform sample, and an
assumption, that moisture content has completely evaporated from tested
sample during testing process, and the sample has not decomposed (e.g.
humid high-silica sand).
Measurement results are always subject to uncertainty related to a sample
and repeatability of used moisture analyzer. In practice, it means that
obtained measurement result may exceed repeatability values provided above.
17.2.3. Drying temperature
Drying temperature has the largest impact on drying time. Temperature value
depends on type of dried substance. Too low drying temperature causes too
low moisture content evaporation (under-dried sample), and consequently
unnecessary extending of measurement time. Too high drying temperature
causes burning of dried sample (sample overheating, chemical
decomposition). Drying temperature of traditional method (using a furnace) is
specified in applicable industry or company standards. Unless standards apply,
then temperature should be adjusted by tests.
On selecting drying temperature value, proceed as follows:
• Determine moisture content in a sample
• Determine temperature of substance chemical decomposition by tests