DETECTOR COMPRISING ONE CATALYSED AND ONE UNCATALYSED METAL OXIDE-SENSOR AND METHOD OF DETECTING

摘要

A detector is described for providing an output signal (Sout) indicative for the presence of scorch in an environment. The detector comprises first and a second sensor (10, 20) for sensingthe presence of gaseous substances and a signal processor (30). The first and the second sensor (10, 20) sense the presence of gaseous substances based on a reversible chemical reaction between a metal-oxide component of the sensor and said substances that results in an observable change in an electrical property of said component. The metal-oxide gas sensitive component of the first gas sensor (10) is uncatalyzed and the metal-oxide gas sensitive component of the second gas sensor (20) is catalyzedby Pd or Pt. The signal processor (30) provides an output signal as a function of a first sense signal (S1_1) indicative for the physical parameter of the first sensor (10) and of a second sense signal (S2_1) indicative for the physical parameter of the second sensor (20).