Star Micronics MG-S Series, Operation Manual

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1 Prior to use MG-S series operation manual
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4
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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 balance 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 balance continuously. When this is the
case, put the specimen in a container equipped with a small mouth and closely
seal the mouth before measurement.
Specimen
temperature
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Difference in temperature between the specimen and the windshield interior
generates convection flow within the windshield, causing a measurement error.
When the specimen temperature is excessively high or low, allow the specimen
temperature to stabilize at the room temperature before measurement. Also, to
prevent the convection flow from arising within the windshield, make the
windshield interior temperature equal to the room temperature before
measurement.
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Measurer’s body temperature also affects measurement result. Handle a
specimen with tweezers instead of directly holding it with fingers and refrain
from putting your hands directly in the windshield during measuring operation.
1-2-4 Precautions related to the main unit of a balance
Operating
precautions
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A dust cover, if equipped, for the balance 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 balance with the cover removed.
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For more stable measurement, it is recommended to energize the balance for
longer than 30 minutes and load the balance a few times with a weight
equivalent to the weighing capacity before measurement.
Calibration
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Calibrate the balance periodically with an external calibration weight. For the
sake of precise calibration, use an external calibration weight weighing nearly
equal to the weighing capacity of the balance.
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Energize the balance for longer than 30 minutes and load the balance a few
times with a weight equivalent to the weighing capacity before calibration.
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Calibration is also needed in the following cases:
When using the balance for the first time,
When using the balance 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 balance is required. In cleaning the balance, take care
for the dust or liquid not to enter into the balance.