Photoelectric smoke detector is a common fire alarm device mainly used to detect smoke in various buildings, factories, and public places. This article will provide a detailed introduction to its technical principles, structure, and application scope.

1 Overview

Photoelectric smoke detector refers to a safety device that uses infrared or visible light to cause combustion substances to react and emit specific gas composition changes for monitoring. It is usually used in public places such as large buildings and underground shopping malls. When a fire occurs, indoor air will be polluted, causing sensors to generate response signals and send signals to warning devices through interfaces to alert people to flee the scene.

2 Technical Principles

The photoelectric smoke detector is composed of high-precision multi-layer filtering lenses. Its core components are LED light sources and receivers. When the material begins to burn, many black solid particle clouds with very small sizes (micron level), but extremely large diameters less than 1 micron are generated during this process (referred to as “white antivirus veils”), which is called smoke.

When “white antivirus veils” of this size enter the interior of the photoelectric smoke detector, they absorb the light between the LED and the receiver and form a dense black cloud in the air. Due to the extremely small distance between the light source and the receiver and the reasonable placement angle, a relatively large signal difference is generated, which ultimately triggers the alarm system.

Photoelectric smoke detectors have advantages such as high sensitivity, stability, and reliability.

3 Structural design

(1) Sensing element: It can convert irregular changes in the surrounding environment into electrical signal output.

(2) Interface board: Achieve wider use by connecting to other facilities.

(3) Dust cover: It can effectively protect the device and extend its service life.

(4) LED light source and receiver: They are the main body and core components of the entire probe.

(5) Lens or filter: By purifying external influences, it improves reaction speed and recognition rate.

4 Application field

Photoelectric smoke detectors are widely used in various public places such as hotels, hospitals, schools, large-scale exhibitions, and transportation.

It can effectively prevent fire accidents, reduce casualties and property losses, and is a very important fire safety equipment.