Troubleshooting - Sartorius YDK03 Mode D'emploi

Troubleshooting

When adjusting,
please note:
Analytical balance:
The sample holder must be removed for
adjustment!
Milligram balance:
The sample holder must be installed for
adjustment!
The formula on the previous page
for determining the specific gravity of
solids is sufficient to obtain an accuracy of
one to two decimal places�
Depending on the accuracy you require,
consider the following error and allowance
factors�
– The density of the liquid causing
buoyancy depends on its temperature
– Air buoyancy during weighing in air
– The change in the immersion level
of the pan hanger assembly when the
sample is immersed
– Adhesion of the liquid on the suspen-
sion wire of the pan hanger assembly
– Air bubbles on the sample
Some of these errors can be corrected by
calculation� To do so, proceed as follows:
– measure the temperature of the
reference liquid and correct its density
accordingly
and
– define the inner diameter of the
container which holds the reference
liquid�
Dependence of the Liquid Density on
Temperature
The density of the liquid causing buoyancy
depends on the temperature� The change
in the density per °C change in tempe-
rature is in the range of
– 0�02% for distilled water
– 0�1% for alcohols and hydrocarbons�
In other words, this can show up in
the third decimal place during specific
gravity/density determination�
To correct the liquid density for tempe-
rature, proceed as follows:
– measure the temperature of the liquid
using the thermometer that comes
with the kit
– use the table at the back of this manual
to find the density of the most com-
monly used liquids, water and ethanol,
at the temperature measured, and use
this density for the value ρ (fl)�
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