3
1-2
For more accurate measurement
To make more accurate measurement, it is necessary to lessen error-causing factors in measurement to
the extent possible. Error-causing factors include not only an instrument error and performance of the
scale itself but also the nature and condition of a specimen, measuring environment (vibration,
temperature, humidity, etc.) and the like. These factors will directly affect measurement result in the case
of a scale with high resolution capability.
1-2-1
Precautions related to measuring environment
Temperature/
humidity/
atmospheric
pressure
→
Try to keep the room temperature constant to the extent possible in order to
avoid condensation and indication drift due to change in temperature.
→
Low humidity is likely to cause generation of static electricity, resulting in
inaccurate measurement.
→
Change of atmospheric pressure is likely to cause change of buoyancy of the air
on the specimen, tare and mechanism of the scale, resulting in inaccurate
measurement.
Vibration/shaking
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It is preferable to locate a measuring room on the first floor or the basement. The
higher the room is, the larger the vibration and shaking become. Therefore, a
highly located room is not suitable for measurement. Rooms near the railway or
road side should also be avoided.
Air draft
→
Places directly exposed to air current from an air-conditioner or to direct sun
generate abrupt temperature change and resultantly cause unstable weight
indication, and therefore, should be avoided.
Gravity
→
The latitude and altitude of a measuring location differentiate the gravity that
affects a specimen, giving a different weight indication to the same specimen.
Electromagnetic
wave
→
At a location where a strong electromagnetic wave generating object is in the
proximity of a scale, the scale is affected by the electromagnetic wave, making
the scale unable to indicate accurate weight, and therefore, such a location
should be avoided.
1-2-2
Precautions related to measuring table
Vibration/shaking
→
Vibrations during measurement destabilizes the indication of measurement
value, leading to inability to make accurate measurement. And so use of a
measurement table that is robust and hardly affected by vibration is required (a
vibration-proof structured table or concrete or stone-made table is suitable). In
addition, placing a sheet of soft cloth or paper under the scale causes shaking or
makes keeping horizontal attitude difficult, and therefore should be avoided.
→
The measurement table should be installed in a position free from vibration to the
extent possible. A corner rather than the centre of a room is less affected by
vibration and therefore more suitable for installation of the scale.
Magnetism/Static
electricity
→
Use of the scale on the table that is subject to magnetism or static electricity
should be avoided.
