Sample gas (max. 600 °C) is continuously taken via a heated sample gas probe, and transported via a heated sample line to the sample pump of the heated sampling unit in the air-conditioned analysis cabinet. Heating to 180 °C prevents condensation in the analysis system. From the sampling unit, the sample gas flows via further heated sample gas lines continuously through the gas cuvette of the actual FTIR analyzer, as well as, through the gas cuvette of the optional ZrO₂ oxygen analyzer.

In the FTIR analyzer, spectra of the gas mix in the infrared spectrum range are recorded at intervals of a few seconds. The generated interferograms are added together and converted to infrared spectra using mathematical Fourier transform routines. The result is the absorption spectrum of the sample gas, averaged over 60 seconds. The concentrations of the individual components are calculated using multivariate-multicomponent analysis.

A connected industrial PC, equipped with the special Calcmet software, handles control of the measurements, analysis of the measured spectra, control of other programmable sequences, and output of the analog and status signals.

FTIR spectroscopy is outstandingly suitable for multicomponent analysis of numerous gas components. However, the oxygen concentration important for emission measurements, and the concentrations of other non-infrared-active gases such as inert gases or hydrogen, cannot be determined in this way.

For measuring O₂, the system can be optionally equipped with a ZrO₂ oxygen analyzer that can be integrated into the Gasmet CEMS as a further 19" rack unit, and controlled using the Calcmet software.

The FTIR method offers the possibility of calculating a "total organic carbon value" from the individual concentrations of several hydrocarbons stored in the Gasmet CEMS standard calibration library. If direct total organic carbon measurement using the FID method is required, a further free 19'' slot of the Gasmet CEMS can be optionally equipped with a FIDAMAT 6.

The cabinet of the Gasmet CEMS analysis system is equipped as standard with an air-conditioning unit mounted on the rear. Power supply versions are available for 115 V AC or 400 V AC.

Gas flow charts and electrical connections

Gasmet CEMS: Gas flow chart including options

Gasmet CEMS: Electrical connections, including options