Gas Filter Correlation CO2 Analyzer
Model N360 - Teledyne Advanced Pollution Instrumentation (TAPI)
The Model N360 measures carbon dioxide (CO2) by comparing infrared energy absorbed by a sample to that absorbed by a reference according to the Beer-Lambert law.
The N360 uses Gas Filter Correlation (GFC) to overcome the interfering effects of various other gases (such as water vapor) that also absorb IR. The analyzer passes the IR beam through a spinning wheel made up of two separate chambers: one containing a high concentration of CO2 known as the reference, and the other containing a neutral gas known as the measure. The concentration of CO2 in the sample chamber is computed by taking the ratio of the instantaneous measure and reference values and then compensating the ratio for sample temperature and pressure. A nitrogen purge system is provided for the GFC wheel assembly to eliminate the effects of ambient CO2, if necessary.