Difference between gas sensor and gas analyser
Are fastLine gas sensors „gas sensors“ or „gas analyzers“?
The difference between a gas sensor and a gas analyser is becoming increasingly blurred. Originally, 20 years ago, NDIR gas sensors only provided an infrared absorption signal. In order to display the concentration of the gas, external software had to calculate this signal with measurement signals for gas temperature and pressure, apply a calibration curve and possibly even make corrections for foreign gases. Temperature and pressure sensors as well as foreign gas were external signals that were processed together in a gas analyser. These analysers often also had a display and were typically installed in a 19″ housing. Devices that combined and output several signals were called ‘gas analysers’ [1].
fastLine sensors with pressure and temperature correction
FastLine sensors have integrated pressure and gas temperature measurement. The physical concentration measurements of the pressure and gas temperatures are carried out sample-by-sample 200 times per second. External corrections are no longer necessary.
Cross-Gas and other compensations
On specific customer request, the influence of background gases can also be corrected, as well as the cross-influence between multiple target gases. These measurements can be read out live as parallel data streams.
On some application, the humidity in the gas has to be considered in the measurement: optionally fastLine sensors feature an H2O sensor, with automatical correction of vater vapor.
fastLine gas analyzers, but much smaller than a 19″ rack
In this sense, fastLine gas sensors fulfil the definition of gas analysers, but are many times smaller. Only the display unit, gas filter and side-stream pump have to be mounted externally. However, we continue to use the term gas sensor, as this is more common in everyday language.
References
[1] T. Singh, U. Bonne, Gas Sensors, Reference Module in Materials Science and Materials Engineering, Elsevier, 2017