Operational Theory | Series 4060 | |
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1.Valve Position
In this mode the analyzer configures the operational valve to back flush the column and charge the sample loop. The Sample Mode is programmed to continue for a 7 minute period by factory default; however, it is usually modified to match the needs of a particular process. The specific timing interval for your system is listed in the Addendum and Testing Results section of Appendix B. It is possible to set the Sample Mode duration up to 25 minutes.
2.Valve Position
In this mode the analyzer configures the sampling valve to feed the gas in the sample loop through the column and to the detector. The eluted sample from the column is fed to the FID for the analysis of the compound of interest in the hydrocarbon stream. If configured to do so, the analyzer may read the detector for a programmed 5 second period at some point within this mode cycle to obtain a baseline reading for further calculation. This mode is usually programmed to continue until the compound of interest is fully eluted from the column. It is possible to set it up to 25 minutes.
During the Analysis Mode, a ‘Peak Detect’ period is programmed at which time the analyzer reads the detector output. The analyzer integrates the peak area during this time in conjunction with the baseline settings to calculate the concentration of the compound of interest. The calculation is performed at the end of the ‘Peak Detector’ period and the result is displayed at the end of Analysis Mode.
2.3 Analyzer Subsystems
The Model Analyzer is composed of three subsystems:
1.Sample System
2.Detector Cell
3.Electronic Signal Processing, Display and Control
2.3.1 Sample System
All components used to control the sample and supporting gases, as well as the combustion portion of the detector cell, are located inside the
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