The basic principle of fire detection is to use a sensitive element to effectively respond to fire information such as fire gas, smoke, temperature and flame, and to determine whether there is a fire in the measured area through the measurement and analysis of fire information parameters.
The composition of automatic fire alarm system
●Alarm area
It should be divided according to fire compartment or floor, an alarm area can be composed of one or several adjacent fire compartments on the same floor.
●Detection area
It should be divided into independent rooms, and the area of one detection area should not exceed 500 square meters;
The length of the infrared light detector area should not exceed 100m;
The length of the cable-type temperature detector area should not exceed 200m;
The length of the air tube temperature detector area should be 20~100m.
The basic form of automatic fire alarm system
●Area alarm system
It consists of fire detector, manual alarm button, regional fire alarm controller or fire alarm controller, fire alarm device and power supply.
●Centralized alarm system
It is composed of fire detector, manual alarm button, regional fire alarm controller or regional display (more than two), centralized fire alarm controller, fire alarm device and power supply.
●Control center alarm system
Fire detectors, manual alarm buttons, regional fire alarm controllers or regional displays (two or more), centralized fire alarm controllers (at least one), fire linkage control equipment (at least one), fire alarm devices, and fire telephones , Fire emergency broadcast, fire emergency lighting and power supply.
Selection and application of fire detectors
1. For places where there is a smoldering stage in the early stage of the fire, a large amount of smoke and a small amount of heat are generated, and there is little or no flame radiation, a smoke detector should be selected.
2. For places where fire develops rapidly and can generate a lot of heat, smoke and flame radiation, temperature detectors, smoke detectors, flame detectors or their combinations can be selected.
3. For places with rapid fire development, strong flame radiation and a small amount of smoke and heat, flame detectors should be selected.
4. For places where flammable gas or flammable liquid vapor is used, produced or gathered, flammable gas detectors should be selected.
