Tethys – EXM400 – Online gass analysator

Modell: EXM400
Produsent: Tethys


Jan Schäffer 2

Jan Schäffer

Petroleum, offshore og reologi
930 66 866

The Model EXM400 gas analyser is specifically designed for stack emission, deNOx and desulphurisation systems, motor exhaust and other chemical processes.

The measurement principle is based on the UV absorption spectrum of gases in the UV range.
The periodic structure of the absorption bands coming from the different levels of rotational energy of the gas molecules is analysed by performing a Fourier Transform on the absorption spectrum with a high speed DSP (Digital Signal Processor).

At the opposite of the FTIR approach where the Fourier transform needs moving optical components, the Fourier transform in the UV range is done by solid state optics and electronic circuits, which constitutes a more reliable solution for a lower cost. The selectivity of the analyser is guaranteed by the typical UV spectrum of each gas.


  • Based on UV Fourier Transform for high selectivity and stability and other algorhythms
  • Ultra-fast response time (< 1 sec)
  • High speed DSP for signal extraction
  • No risk of interferences or quenching effects with CO, CO2, H2O
  • No converter, no maintenance
  • 10-years lamp lifetime


Selger Jan Schäffer