Flame detector

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A flame detector is a detector that uses optical sensors to detect a flame.

Contents 1 Types 1.1 UV flame detection 1.2 IR flame detection 1.3 UV/IR flame detection 1.4 IR/IR flame detection 1.5 IR/IR/IR flame detection 1.6 Video flame detection 2 Applications 3 See also 4 References

[edit] Types

[edit] UV flame detection

Ultraviolet detectors work with wavelengths shorter than 300 nm. Detect flames at speeds of 3-4 milliseconds due to the UV high-energy radiation emitted by fires and explosions at the instant of their ignition. False alarms from random UV sources such as lightning, arc welding, radiation, and solar radiation occur.

[edit] IR flame detection

IR flame detectors work within the infrared spectral band. The mass of hot gases emits a specific spectral pattern in the infrared spectral region which are sensed with a thermographic camera. False alarms by any other “hot” surface in the area occur.

[edit] UV/IR flame detection

UV and IR flame detectors compare the threshold signal in two ranges and their ratio to each other to confirm the reliability of the fire signal to minimize false alarms.

[edit] IR/IR flame detection

Dual IR (IR/IR) flame detectors compare the threshold signal in two ranges

[edit] IR/IR/IR flame detection

Triple IR flame detectors compare three specific wavelength bands within the IR spectral region and their ratio to each other to confirm the reliability of the fire signal to minimize false alarms.

[edit] Video flame detection

CCTV or (web)camera video detection (0,4 tot 0,7µ). Like humans the camera can be blinded by smoke or fog.^[1]

[edit] Applications

UV/IR flame detectors are used on hydrogen stations^[2]

[edit] See also

• Active fire protection

[edit] References