4
1-2-3
Precautions related to a specimen
Static
electricity
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In general, synthetic resin- and glass-made specimens are high in electric insulation,
and so easily charged electrically. Weighing an electrically charged specimen makes
the indication value unstable, reducing the reproducibility of the test result. Therefore,
neutralize an electrically charged specimen before measurement.
Magnetism
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Specimens affected by magnetism show different weight in a different position of the
weighing pan, reducing the reproducibility.
When weighing a magnetized specimen, either eliminate the magnetism from the
specimen or place a setting plate on the weighing pan to distance the specimen from
the weighing mechanism of the scale so that the mechanism may not be affected by
the magnetism.
Moisture
absorption/
Evaporation
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Measuring a moist or evaporating (vaporizing) specimen increases or decreases the
indication value of the scale continuously. When this is the case, put the specimen in
a container equipped with a small mouth and closely seal the mouth before
measurement.
1-2-4
Precautions related to the main unit of a scale
Operating
precautions
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A dust cover, if equipped, for the scale may possibly make the weight indication
unstable due to static electricity charged on the cover at a low humidity. When this is
the case, wipe the cover with wet cloth or use antistatic agent or use the scale with
the cover removed.
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For more stable measurement, it is recommended to energize the scale for longer
than 30 minutes and load the scale a few times with a weight equivalent to the
weighing capacity before measurement.
Adjustment
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Calibrate the scale periodically with an external adjustment weight or internal
adjustment weight. For the sake of precise calibration, use an external adjustment
weight weighing nearly equal to the weighing capacity of the scale.
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Energize the scale for longer than 30 minutes and load the scale a few times with a
weight equivalent to the weighing capacity before adjustment.
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Adjustment is also needed in the following cases:
When using the scale for the first time,
When using the scale after a long period of non-use,
When changing a place of installation, and
When there was a large change in temperature, humidity or atmospheric pressure.
Maintenance
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Attachment of dirt such as powder or liquid to the weighing pan or pan base will
cause measurement error or unstable weight indication. For that reason, frequent
cleaning of the scale is required.
