Infrared point sensor: Difference between revisions

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Latest revision as of 04:48, 7 May 2025

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{{Short description|Point gas detector}}

A '''infrared point sensor''' is a point [[gas detector]] based on the [[nondispersive infrared sensor]] technology.

{{more citations needed|date=April 2025}}

An '''infrared point sensor''' or point infrared (IR) detector is a type [[gas detector]] that uses infrared absorption at specific wavelengths to detect changes in gas composition in air.<ref>{{Cite web |author=Editorial Staff |date=2017-03-31 |title=Point IR Detectors Vs Open Path IR Detectors |url=https://instrumentationtools.com/point-ir-detectors-vs-open-path-ir-detectors/ |access-date=2025-04-09 |website=Inst Tools |language=en-us}}</ref> Gases that can be detected include hydrocarbons, allowing infrared point detectors to be used in safety applications to detect the presence of flammable gases at low levels and shut down equipment as needed to prevent fire or explosion.

==Principle==

Dual source and [[Passive infrared sensor|dual receivers]] are used for self compensation of changes in [[alignment]], light source intensity and component efficiency. The transmitted beams from two [[infrared]] sources are superimposed onto an internal [[beam splitter]]. 50% of the overlapping sample and reference signal is passed through the gas measuring path and reflected back onto the measuring detector. The presence of combustible [[gas]] will reduce the intensity of the sample beam and not the [[reference beam]], with the difference between these two signals being proportional to the concentration of gas present in the measuring path. The other 50% of the overlapped signal passes through the beam splitter and onto the [[compensation detector]]. The compensation detector monitors the intensity of the two infrared sources and automatically compensates for any long term drift.

[[Mean time between failurehjghhgbkgkusfailures]] may go up to 15 years.

==Micro heaters==

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==Range==

[[Toxic]] gases are measured in the low parts per million ([[Parts- per notationmillion|ppm]]) range. Flammable gases are measured in the 0 - 100 % [[lower flammable limit]] (LFL) or [[lower explosive limit]] (LEL) range.

==See also==

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* [[Service life]]

* [[ATEX directive]] II 1G EEx ia IIC T6

* [[Infrared gas analyzer]] - for gas monitoring and analysis, rather than leak detection.

* [http://www.innovision.us/RF02-16ATEX.htm Atex certified Reed Sensor]

== External links ==

*[http://www.fs-business.com/FAQ/FAQGasDetection.asp#What%20are%20the%20requirements%20for%20all%20point%20detection%20methods? Point detection]

==References==

{{Reflist}}

[[Category:Gas sensors]]