Photoelectric smoke alarm's work principle is to use its internal optical maze, equipped with infrared tube. When the environment is smokeless, the infrared receiving tube cannot receive the infrared light emitted by the infrared transmitting tube. When the smoke enters the optical maze, the receiving tube receives the infrared light through refraction and reflection and converts it into an electrical signal. The detection circuit amplifies the electrical signal and sends an alarm when the concentration exceeds the set threshold.
The volume of smoke particles generated by smouldering fire is relatively large, and the larger smoke particles diffuse light more strongly. In this case, the photoelectric smoke alarm will alarm before the ion smoke alarm. For example, a fire in a house usually produces a lot of smoke in the initial stage. It is recommended to install a photoelectric smoke alarm in such places.