Metrohm 892 Professional Rancimat - Manual (Page 9)

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1 Introduction
892 Professional Rancimat
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1 Introduction
1.1 Instrument description
The 892 Professional Rancimat is a computer-controlled measuring device
for determining the oxidation stability of samples containing oil and fat.
It is equipped with two heating blocks each with 4 measuring positions.
Each block can be heated individually, i.e., 4 samples can each be mea-
sured at two different temperatures or 8 samples at the same tempera-
ture. The measurements at the individual measuring positions can be
started individually for this.
The 892 Professional Rancimat is controlled by means of the StabNet
computer software and a computer that is connected via the USB inter-
face. Up to 4 instruments can be controlled and monitored by each com-
puter, hence allowing a maximum of 32 samples to be analyzed at the
same time. The evaluation algorithm of the computer software determines
the break point of the Rancimat curve and thus the induction time fully
automatically. Besides the induction time, the so-called stability time,
i.e., the time until a defined conductivity change has been achieved, can
also be determined. In the case of conductivity changes (stages) which do
not have anything to do with the autoxidation, the evaluation can be sus-
pended for definite time intervals. The results determined can be further
processed mathematically. In particular, the induction times can be con-
verted to the standard temperatures defined in the respective standards.
Each Rancimat curve can also be evaluated manually. A computer-sup-
ported tangential method is available for this, in which you can position
the tangents anywhere on your curves. This makes evaluations possible in
extreme cases as well.
The results of the determinations are saved in a database together with all
method and determination data. Determinations can be searched for,
sorted, filtered, exported and printed in the Database program part.
Apart from graphically displaying individual and multiple curves, the soft-
ware is also capable of conducting recalculations with changed parame-
ters and extrapolating the results to a certain temperature.