NON-DISPERSIVE INFRARED GAS ANALYZER

摘要

The invention relates to a NDIR-gas analyser comprising an infrared radiation source (1), a measuring vessel (3) containing a gas mixture (4) having a measuring gas component (5) that is to be detected, and a detector device (7) that is arranged behind the measuring vessel that can detect the influence of ageing of the radiation source (1) and optionally dirt deposits in the optical radiation path without interrupting measuring. According to the invention, at least one optopneumatic detector (15) is arranged in the beam path of the radiation source (1), said detector being filled with any gas (16) when arranged between the radiation source (1) and the measuring vessel (3). The concentration of measuring gas components is lower in the detector (15) than in the measuring vessel (3) if filled with the measuring gas components, and said detector is filled with a gas when arranged between the measuring vessel (3) and the detector device (7), the absorption spectrum of the detector being outside of the spectrum of the measuring gas components (5) and other transversal gases in the gas mixture (4). The measuring signal (12) of the detector device (7) is corrected by the detector signal (21) generated by the detector (15).