New applications of tin oxide gas sensors: II. Intelligent sensor system for reliable monitoring of ammonia leakages

  • Jerger A
  • Kohler H
  • Becker F
 et al. 
  • 21

    Readers

    Mendeley users who have this article in their library.
  • 60

    Citations

    Citations of this article.

Abstract

Cooling plants have to be monitored due to coolant leakages for well-timed signalling if predefined concentration levels are exceeded. Available monitors mostly suffer on long-time stability or insufficient gas identification capability and both give reasons for numerous false alarms. A prototype of an intelligent field suitable ammonia leakage monitor was developed which may overcome this drawback in future. The microprocessor supported hardware operates a sensor head with three tin oxide-based gas sensors simultaneously. Capability of gas identification and concentration determination of TGS-type gas sensors could be considerably improved by periodic variation of the working temperature of the sensor elements, simultaneous sampling of the sensitive layer conductance and application of a rather simple new algorithm for analysis of the resulting conductance-time profiles (CTP). Test results of gas analysis experiments at various ammonia concentrations and humidities based on a (4×3) matrix-calibration field are presented. The remarkably good accuracy of ammonia monitoring at various concentrations and humidities and the excellent capability of ammonia identification without recalibration was demonstrated by long-term test experiments over several weeks. © 2002 Elsevier Science B.V. All rights reserved.

Author-supplied keywords

  • Ammonia
  • Gas sensor
  • Humidity
  • Identification
  • Monitor
  • Periodic temperature
  • Tin oxide

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free