Smoke detectors, also known as smoke sensitive fire detectors, mainly used in fire protection systems, also used in the construction of security systems, is a typical firefighting measures from space to civilian measures of equipment, mainly by monitoring the concentration of smoke to achieve fire prevention.Different types of smoke sensors have different principles
The fire starting process is generally accompanied by smoke, heat and light three combustion products. In the early stage of a fire, a large amount of smoke is produced because the temperature is low and the substance is mostly in the negative combustion stage. Smoke is one of the important features of early fires, and smoke sensitive fire detectors were developed to take advantage of this feature.
Currently, two smoke detection technologies are commonly used for smoke detectors, namely Ionization system: a small amount of radioactive material is mixed between two conductive plates. This ionizes the air and allows the current to flow. When smoke enters the chamber, it reduces the current flow and triggers an alarm.
Photoelectric smoke detector: uses light to detect fire. Inside the detector, there is a light-sensing chamber that uses light to detect smoke. When smoke is detected, it refracts LED into the photodetector. When the light beam reaches this sensor, an alarm is triggered.