A NEW NDIR ANALYZER INCORPORATING A COMPLETE SYSTEM CALIBRATION

摘要

A double pass in-situ NDIR analyzer has been developed utilizing the incremental addition of two or more different and known calibration standards. This automatically calibrates the complete system in the presence of sample. Potential interferences and alignment variations are detected and eliminated. This calibration takes only a few seconds and can be performed on a minute by minute basis if desired. The periodic internal instrument zero, span, and reference standards validation frequency is operator selectable, and only requires the analyzer to be off-line momentarily. This calibration scheme assures continuous zero and span stability, and requires no operator assistance.