Metrohm 893 Professional Biodiesel Rancimat - Manual (Page 48)

6.1 Problems
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893 Professional Biodiesel Rancimat
Problem Cause Remedy
The connection to the
measuring vessel is not
mounted correctly. Ensure that no air can escape through leaks
when transferring from the reaction vessel to
the measuring vessel.
The temperature in differ-
ent positions of a heating
block differs, as sample has
burnt on at one or more
places in the recess of the
heating block. If necessary, carefully remove contamination
from the cold heating block.
The sample is not homoge-
nous. Homogenize the sample.
The stability times
are not reproducible
for multiple determi-
nations. The cell constant was not
determined or does not
correspond to the value
entered. ￭ Determine the cell constant.
￭ Make sure that the assignment of the con-
ductivity sensors is correct, so that the
determined cell constant actually corre-
sponds to the measuring cell used.
￭ Make sure that the measuring cell is not
contaminated. Clean if necessary.
The conductivity measuring
cell is contaminated. Check the measuring cell and, if necessary,
clean.
See also: The induction
times are not reproducible
for multiple determina-
tions.
The induction time
is longer/shorter
than expected. The temperature is not
selected correctly. ￭ Make sure that the correct method for the
determination has been selected.
￭ Check whether the Sample temperature
and the Temperature correction are
indicated correctly in the method.
See also: The induction
times are not reproducible
for multiple determina-
tions.
The stability time is
longer/shorter than
expected. The conductivity change is
not correctly defined. Make sure that the value defined for the con-
ductivity change in the method is correct.
See also: The stability times
are not reproducible for
multiple determinations.