INFICON Explorer Portable Gas Chromatograph - Manual (Page 178)

Method Development
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Peak retention times are measured when the slope changes from positive to negative
(the peak maxima).
Peak areas are calculated by summing the area slices beneath the signal and
subtracting the area below the line connecting the start and end points.
If Automatic Integration is enabled, Explorer will enter the values automatically
in the Integration Method dialog box in the Analyzer menu. You can enter the
Up/Down Slope and Minimum Height values if automatic integration is disabled.
The slope is calculated from a five point moving average and is compared with the
effective Up and Down Slope sensitivities to start and stop the integrator.
To set up the integration, select Integration Method from the Analyzer menu.
The Integration Method dialog is displayed.
Automatic Integration
For most analyses automatic integration will give the best results. If, however, the
signal is not representative during the five second period, then the peak recognition
factors Up Slope, Down Slope and Minimum Height may not be calculated correctly
for the chromatogram. In this case it may be necessary to set the integration
parameters manually.
The choice of initial Up/Down Slope and Filter can require some expertise. Explorer
automates this procedure as the Up/Down Slope, Minimum Height, and Filter
options are set automatically if automatic integration is enabled.