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Errors due to air flow and measures to take
Where the influence of ambient air flow is
great such as: close to an air conditioner, door
or passage way. Even very subtle air flow that
is hard to be detected may influence the
weighing operation.
Avoid those areas as a weighing site.
If weighing is to be performed in such an
area, use a breeze break or take other
appropriate measures.
Where the influence of heat or drafts is great
Eliminate temperature differences
between a sample and the environment.
When a sample is warmer (cooler) than
the ambient temperature, the sample will
be lighter (heavier) than the true weight.
This error is due to a rising (falling) draft
around the sample.
Do not touch the sample directly with your
hand. Use tweezers or other tools.
If you touch the sample, the same type
error described above will occur.
Do not perform weighing where it is exposed to direct sunlight. Weighing errors may
occur due to sudden temperature change or drafts.
Errors due to vibration and measures to take
Where the influence of vibration is great, such as:
(1) Soft ground (2) Second or higher floor (3) Near center of a floor far from pillars (4) Seismic
isolated structures (5) Near tall buildings.
In the areas listed above, the scale may yield unstable weight values on windy days or after an
earthquake. Especially in case of (4) and (5), weight values may be unstable for a long period of
time because of long lasting low-frequency vibration after strong winds or an earthquake.
Errors due to other causes and measures to take
Change in temperature or humidity
A sudden change in temperature or humidity can generate a draft and cause the balance to
absorb or exude moisture, which leads to unstable displays.
Avoid sudden change in temperature or humidity.
Use an air conditioner or humidifier to control the temperature or humidity.
Magnetic material
The balance uses a strong magnet as part of the balance assembly, so use much care when
weighing magnetic materials.
Place a non-magnetic object such as aluminum or brass between the sample and the
balance to keep an appropriate distance between them while weighing.
Draft
40 C
20 C
