The sensor of the flue gas probe is based on the principle of solid
electrolytes (zirconium dioxide). The free oxygen ion movement
begins at temperatures of more 500 °C (solid electrolyte potentiometric
method).
The sensor is heated. The oxygen concentration is calculated from
the cell voltage and the temperature according to Nernst's law.
The analyser consists of a probe and an evaluation unit. The probe
is directly immersed into the gas to be measured (in situ). The probe
tip should be approximately in the centre of the chimney. The
electronic system is equipped with a cable (5 m) with plug which is
plugged directly into the probe. The evaluation unit is operated by
means of the keypad and the display. The system displays the
current oxygen concentration in percent by volume (0-21 % O2 )
and the temperature of the measuring cell.
