The working principle of photoelectric smoke detectors

Photoelectric smoke detectors are mainly used to detect the concentration of smoke generated when a fire occurs in the detection area of the detector. The working principle of photoelectric smoke detectors is: there is a black maze (photoelectric detection chamber) inside the detector, and there is an infrared light emitting tube and a photosensitive tube inside the maze. The infrared light emitting tube and photosensitive tube are shielded and isolated through the maze. Under normal circumstances, due to the isolation of the maze, The photosensitive tube cannot receive the infrared light emitted by the infrared light emitting tube, and the detector outputs a normal working signal;

When particles such as smoke and dust float into the photoelectric smoke detectors chamber, the infrared light emitted by the infrared light emitting tube is reflected or refracted by the smoke or dust particles and received by the photosensitive tube. The voltage of the photosensitive tube changes, and the photoelectric smoke detectors output an alarm signal that is opposite to the normal working state;