What is UV/IR Flame Detection?
The dual spectrum UV/IR technology employs a solar blind UV sensor with a high signal-to-noise ratio and a narrow band IR sensor. The UV sensor itself is a good fire detector but it is easily activated by alarm stimuli such as arc welding, lighting, X-rays and solar spikes. In order to prevent false alarms caused by these sources, an IR sensing channel was added, working at 2.7micron or 4.1- 4.6micron spectral ranges. These IR spectral channels exhibit the spectral signature characteristic to fire and, in addition to the fire’s UV spectral signature, are considered reliable for most mid-range applications. However, even this advanced technology has its limitations, since each type of fire has its own specific ratio of UV to IR output. For example, a hydrogen flame generates a lot of UV radiation with very little IR, while a coal fire will generate little UV radiation and a high amount of IR radiation. Hence the dual UV/IR detector must combine both signals and compare them accordingly
