Non-Dispersive Infra-Red (NDIR) detectors are the industry standard method of measuring the concentration of carbon oxides (CO & CO2).
Each constituent gas in a sample will absorb some infra red at a particular frequency. By shining an infra-red beam through a sample cell (containing CO or CO2), and measuring the amount of infra-red absorbed by the sample at the necessary wavelength, a NDIR detector is able to measure the volumetric concentration of CO or CO2 in the sample.
A chopper wheel mounted in front of the detector continually corrects the offset and gain of the analyser, and allows a single sampling head to measure the concentrations of two different gases.
The Cambustion Fast NDIR uses a unique sampling system, coupled to miniaturised NDIR technology to give millisecond response times.
The Cambustion Fast NDIR has two remote Sampling Heads controlled by a Main Control Unit, and is capable of sampling CO & CO2 simultaneously in two locations.
See Applications & Sample Data
출처: <http://www.cambustion.com/products/ndir500/operating-principle>
