The combustible gas detector and alarm system：combustible gas alarm controller, combustible gas detector and fire sound and light alarm. It can alarm in advance. When the concentration of leaking combustible gas in the protected area is lower than the lower explosion limit. Thereby preventing the leakage of combustible gas Fire and explosion accidents caused by the occurrence.
System application place
The detection and alarm system is suitable for the detection of combustible gas concentration in places where combustible gas or combustible liquid vapor is used, produced or collected. It sends an alarm signal. Before the concentration of leaked or accumulated combustible gas reaches the lower explosion limit. To remind professionals to eliminate fire and explosion hazards and realize fire Early prevention to avoid fire and explosion accidents.
System composition
The detection and alarm system is an independent subsystem of the automatic fire alarm system, which belongs to the fire early warning system.
(1) Combustible gas alarm controller
The alarm controller is a device. it is used to supply power to the connected detection, receive the alarm signal from the combustible gas detection , send out sound and light alarm signals and control signals, indicate the alarm location, and record and save the alarm information.
(2) Combustible gas detection
The combustible gas detection is a device that can respond to the leaked combustible gas, automatically generate an alarm signal and transmit the alarm signal and the leaked combustible gas concentration information to the combustible gas alarm controller.
How the system works
When a detection leak occurs, the combustible gas detection installed in the protected area will convert the concentration parameter of the leaked combustible gas into an electric signal. After data processing, the combustible gas concentration parameter information is transmitted to the combustible gas alarm controller.
The combustible gas detection directly makes the alarm judgment. Of the concentration of the leaked combustible gas and transmits the alarm information to the combustible gas alarm controller. After the combustible gas alarm controller receives the information of the detection. after confirmation and judgment, it displays the position of the leak alarm detection and the leakage combustible gas concentration information, records the alarm time of the detection, and drives the installation at the same time. The sound and light alarm device sends out sound and light alarm to warn the personnel to take corresponding measures.
If necessary, the gas valve can be controlled and shut off to prevent further gas leakage.
system design
The combustible gas detection and alarm system is an independent subsystem. Which belongs to the fire early warning system and should be composed independently.
The combustible gas detector should be connected to the combustible gas alarm controller, and should not be directly connected to the detector circuit of the fire alarm controller.
The combustible gas alarm controller transmits the alarm signal to the graphic display device of the fire control room or the centralized fire alarm controller, but its display should be different from the fire alarm information; the combustible gas detector involved in process control in the petrochemical industry can be connected DCS and other production control systems, but their alarm signals should be connected to the fire control room.
(1) Setting of combustible gas detector
The combustible gas detector that detects the gas density less than the air density should be installed at the top of the protected space, and the combustible gas detector that detects the gas density greater than the air density should be installed at the lower part of the protected space. It detects combustible gas with a gas density equal to the air density. The detector can be set in the middle or the top of the protected space.
The combustible gas detector should be installed near the place where combustible gas may be produced. The protection radius of the point-type combustible gas detector should comply with the relevant regulations of the “Petrochemical and Chemical Combustible Gas and Toxic Gas Detection and Alarm Design Code” (GB50493-2009). The length of the protection area of the linear combustible gas detector should not be greater than 60m.
(2) Setting of combustible gas alarm controller
When there is a fire control room, the combustible gas alarm controller can be installed near the protected area; when there is no fire control room, the combustible gas alarm controller should be installed in a place with personnel on duty. The setting of the combustible gas alarm controller should meet the installation and setting requirements of the fire alarm controller.