ABB PGC2000 Operation And Service Manual page 95

RF = CC/A, for peak area analysis of a given component
RF = CC/H, for peak height analysis of a given component
• Normalized, in which the controller calibrates the analyzer against the external standard, then
calculates the sum of all peak areas and determines the percent contribution of each component
peak
Normalized calibration requires you to provide the component concentration value of each
component to be analyzed in a calibration stream. The system performs an analysis of the
stream, obtaining corrected peak area counts for each component and for the total stream. A
response factor is generated as:
RFi = (Atot/Ai)CCi, where "Ai" is for individual component, "Atot" for total
• Indirect External Standard, in which the controller uses a previously developed or literature-
derived set of response factors to calculate the relationship between the key component and
each of the other components. This mode is used when the components cannot be individually
calibrated. Calibrating the key component of the standard sample updates only the K-factor,
while the other components are updated through the relationship of the various components.
Indirect External Standard calibration requires you to provide the concentration of a specific
component in a calibration stream, plus the relative response factor (RRF), for each component
to be measured. The system performs an analysis of the calibration stream, obtaining a
corrected peak area value for the calibration component (Ac). A K-factor is then calculated for
the stream, as follows:
K = (CCc/Ac)(1/RRFc), where subscript "c" is for the calibration component
Component concentration values are then obtained based on corrected peak area values
following an analysis:
CCi = (Ai)(K)(RRFi), where subscript "i" is for the individual component
As part of the calibration you can also select primary and secondary calibration streams, benchmark
stream, multiplier exponent, and K-factor:
•
primary calibration stream has a default setting in the analyzer of stream 10. This does not need
to be set or changed (but it can be changed if desired).
•
secondary calibration stream is necessary when all standard components are not compatible in
the same container.
You can only assign a secondary calibration stream to a method table if the GCC
uses the External Standard calculation technique. Normalized and Indirect
External Standard calculation require a single calibration stream.
•
multiplier exponent is an exponential value which allows the analyzer to present the response
factor as an easily identified number (e.g., if response factor is 0.000005, analyzer might show
response factor = 5 and multiplier exponent = 6).
•
K-factor is used with the indirect external standard to provide a means of relating the calibration
standards of all components when only one component can be measured. Once the relationship
2000-OSM, F1
or
NOTE
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