Metrohm 746 VA Trace Analyzer - Manual (Page 221)

5.5 Operation
746 VA Trace Analyzer / 747 VA Stand
5-70
Softkeys Meaning
from
proc.
Recalculation using manually modified experimental data ( processed ).
The determination is reevaluated with the aid of the experimental data
modified by spike elimination and the modified method parameters.
from
eval.
New content and formula calculation using evaluation values of
substances (EV values).
from Op.
sequence
New content and formula calculation with modified method parame-
ters referring to sample quantity, dispensed volumes or concentra-
tions of solutions.
The following should be noted with regard to the different types of
recalculation:
• A recalculation from orig. or from proc. must always be
initiated if method parameters have been modified which affect
the determination of the EV values (e.g.
Recognition , Baseline ,
Evaluation ).
• A recalculation from Op.sequence must always be initiated when
the dilution calculation should be redone owing to modified
method parameters.
• A recalculation from eval. is advisable if only certain EV values
have been suspended or formulae changed.
Storage of recalculated determinations
Recalculated determinations are not stored automatically. To store a
recalculated determination with its modified method, it must be copied
to the determination storage or to the data card.
Dilution recalculation with Dosimats/Dosinos
Before starting a recalculation from Op.sequence with modified pa-
rameters affecting the dispensing operations with 685 Dosimats/700
Dosinos make sure that the same Dosimats/Dosinos with the same
Exchange/Dosing units are attached to the 746 VA Trace Analyzer as in
the original determination, otherwise deviations in the result calculation
could arise.
Recalculation of determinations from older software versions
Because of a modified smoothing procedure the recalculation of
determinations from the 693 VA Processor with a program version
≤ 5.693.0021 may lead to peak evaluation values which differ by ≤ 5%.
Data processing Determi-
Recalculation
nation from
orig.
from
proc.
from
eval.
from
Op.seq.
1. Data acquisition → original l
2. Spike elimination → processed l l
3. Smoothing → smoothed l l l
4. Recognition l l l
5. Baseline calculation → subtracted l l l
6. Height/area calculation → EV values l l l
7. Dilution calculation l l
8. Calibration → MC values l l l l l
9. Formula calculation → final results l l l l l