Metrohm 790 Personal IC - Manual (Page 106)

4.4 Methods
790 Personal IC
97
Setup
Tab
Setup
of
Integration parameters
window with integration parameters.
The two most important of these parameters for peak recognition are
Width and Slope .
If the signal-to-noise ratio of the chromatogram is high enough (e.g.
100:1 or higher), the integration algorithm is not too sensitive to
changes in integration parameters. On the contrary, if the baseline
noise is high, careful tuning of these parameters may be needed.
Number of peaks Number of peaks detected (read-only).
Delay Time delay before starting peak detection
(in min).
Entry range: 0… … … …1440 min
Width Peak width (at the baseline, in s).
This parameter is used for setting baseline start
and end points. If this value is too low, exces-
sive narrow peaks are detected from the base-
line noise. If it is too large, several adjacent
peaks or baseline drift can be integrated as a
single peak. For an optimal evaluation, it is rec-
ommended to enter the width of the narrowest
peak on the chromatogram (normally 2…10 s).
Entry range: 0.1… … … …480 s
Slope Threshold for peak recognition.
The value of the first derivation (slope) of the
curve is divided by the baseline noise (which is
estimated using a special algorithm) and the
result is compared with the Slope threshold
value. Reasonable range of Slope parameter is
0.5...25.
Entry range: 0.1… … … …400