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(a) Illumination uniformity (Correct) (b) Unbalanced brightness (Prohibited)
Pic 2.7-8 Illumination condition recommendation
Obstacles object factor
Video Fire Detection System is processing video analysis to recognize the fire and smoke. If
the image is blocked by obstacles, the video analysis cannot be correctly performed. Please
notice the picture from the camera is clear and not blocked by obstacles.
Air flow factor
Air flow condition plays an important role in smoke detection as air flow varies the physical
characteristics of smoke. Different air flow conditions alter fire and smoke exercise.
Installer will need to take Air Flow as a factor for correct detection on the fire and smoke.
Lens clarity factor
Lens is the eye to the camera as the eyes to human. The blemish on the lens blocks the
image which affects the detection precision of VFDS. The clarify of lens is required
for precious detection. Do not touch the surface of lens with polluted materials, such
as fingers, towel or hard cloth, to avoid scratch, mist and stains.
Others
The cameras detection footprint is not recommended to cover large areas with large
proportion of moving objects. Frequently moving objects in large proportion in the
detection footprint may cause false alarms more easily, referring to 2.7-9(a). 2.7-9(b).
Keep the cameras away from the detection target is strongly recommended. The camera
is suggested to be installed in high-risk and vacant area, as pictures 2.7-9(c) and
2.7-9(d).
