Flam IR sensors - how they work

Infrared emitters within the sensor each generate beams of IR light . Each beam is of equal intensity and is deflected by a mirror within the sensor on to a photo-receiver, which measures the level of IR received. The “measuring” beam, with a frequency of around 3.3μm, is absorbed by hydrocarbon gas molecules, so the beam intensity is reduced . The “reference” beam (around 3.0μm) is not absorbed, so arrives at the receiver at full strength. The %LEL of gas present is determined by the difference in intensity between the beams measured by the photo-receiver.

[@avicohen2190]

do you have technucal details for your flame EX detectors as: flame 2300,flame 5000, 40/40I

[@user-ll2zu7ri4f]

It is gas detecter not flame

[@avicohen2190]

correct=technical details//

[@shivamsahil3660]

THEN What's the use of 3 um emitter, even if its not there still it will detect.

[@alikhanzulkashov4438]

I think it should probably work as a reference beam to show whether or not gas concentration exceeds the LEL%