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Moisture Grain &
Hay : Grain Related Questions
hy is Grinding
and Compressing a grain sample advantageous?
During harvesting and drying, the moisture level within individual
grains may not be evenly distributed. Grain that has been exposed to
rain showers would have a wet husk, but it may be sufficiently dry at
its core. Conversely, grain from the drier may appear to be very dry on
its surface, but may still have excessively high moisture levels within
it.
Representative and reliable moisture readings can only be obtained under
these circumstances by measuring a ground sample that has been
compressed onto the measurement cell of the moisture meter. The grinding
ensures that unrepresentative moisture levels on the surface do not skew
the measurement and the compression ensures consistency and
repeatability.
What is A.T.C.?
Automatic Temperature Correction (ATC) is a facility that corrects the
moisture measurement of a sample with respect to its temperature.
Protimeter moisture meters are calibrated at 20°C; if the temperature of
the sample is significantly above or below this figure, the moisture
measurement requires correction to account for changes in electrical
characteristics.
All Protimeter moisture meters automatically correct for the effects of
temperature on moisture measurements. For this reason, Protimeter
recommend that the ATC function is always active when measuring the
moisture level of crop samples. ATC should only be deactivated when
using the ‘Quickcheck’ device to check the calibration of the instrument
with respect to factory settings.
How can I measure the moisture content in crops
not pre-programmed in my instrument?
If the crop to be tested is not pre-programmed into the instrument, a
moisture reading is taken using the 0-100 relative scale. The value is
noted, and reference is made to the Protimeter Crop Calibration Data
table. This table, supplied with all Protimeter moisture meters, enables
the user to convert the relative reading into the actual moisture
content value.
How can I check the calibration of my grain
moisture meter?
A 'Quickcheck' device is supplied with all Protimeter grind-compress
moisture meters for checking the instrument’s set up and calibration. If
the meter readings are not within the stated tolerance as given in the
instruction manual, you are advised to return your instrument to the
Protimeter Service Centre for servicing.
Can I measure temperature of grain in the store
with my Protimeter moisture meter?
Most Protimeter grain meters can be used with optional temperature
probes for this purpose. To find out if a Temperature Probe is available
for your existing meter, please contact us and advise what model of
instrument you are using.
What are the requirements for safe grain
storage?
There are four key requirements that must be satisfied if grain is to be
stored safely:
1.The moisture content of the grain should not exceed 15%.
2.Temperature gradients within the grain should be evened out and the
bulk temperature should be reduced to the lowest possible level.
3.The grain must be protected from moisture ingress and condensation.
4.The grain must be protected from pests including insects, mites, birds
and rodents.
For further information on these topics please refer to the Protimeter
booklet CARE OF GRAIN that can be downloaded from the Data Sheets
section of this site.
What can I do if there is a discrepancy between
my moisture meter reading and that of my merchants or other party?
There are many variables that subtly affect the calibration of moisture
meters including measurement technology, crop variety, and soil types,
growing conditions and geographical regions. One has to accept,
therefore, that moisture meter measurements are subject to working
tolerances, and modest discrepancies between different meters are to be
expected.
Protimeter grain moisture meters have a facility to adjust calibrations,
if required, to account for these variables. For example, pragmatic
farmers may choose to compare the results obtained on their moisture
meter with those of their merchant on a sample at the beginning of the
season. If there is a discrepancy, they may agree to match their meters
by adjusting the calibration of particular crops.
What is the ideal storage temperature for
grain?
The grain temperature affects the relative humidity in the voids between
the kernels. Low temperatures reduce the amount of water available to
mites and moulds and vice versa, so the storage temperatures should be
reduced to minimum sustainable levels because, practically speaking,
cooling has the same effect as drying.
A graph showing the relationship between temperatures and moisture
levels is reproduced in the Protimeter booklet CARE OF GRAIN that can be
downloaded from the Data Sheets section of this site.
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