Common gas fire extinguishing controllers
How fire detectors work
Fire detectors can be roughly divided into three types: smoke detectors, temperature detectors, and other detectors. Fire detectors are an important part of the automatic fire alarm system of buildings, also called probes or sensitive heads. Its task is to detect the occurrence of fires, send fire signals to the alarm system, and alert people. When a fire occurs, it will inevitably produce smoke, flames or high temperatures, and the detector is very sensitive to these, and will change the usual normal state due to contact with them, causing changes or displacements in current, voltage or mechanical parts, and then through amplification, transmission and other processes, send fire signals to the fire control room, and display the location and location of the fire.
1) Temperature detector.
One is to use the characteristics of metal thermal expansion and contraction, under normal circumstances, the circuit of the detector is in a disconnected state, when the ambient temperature rises to a certain value, the expansion and extension of the metal make the circuit turn on and send a signal; The other is to use the characteristics of fusible metal to fix a low melting point alloy in the detector circuit, when the temperature rises to its melting point, the metal melts, with the help of the force of the spring, the contact is contacted, the circuit is turned on, and an alarm signal is issued; There is also a temperature difference type, which induces an alarm when the rate of heating exceeds a certain value.
Common temperature-sensing fire detectorsSmoke detectors.
One is the ion smoke detector, once the smoke escapes into the external ionization chamber, interfering with the normal operation of charged particles, changing the current and voltage, and destroying the balance between the internal and external ionization chambers, the detector will induce this and send an alarm signal; The other is a photoelectric smoke detector, it has a light-emitting element and a photosensitive element, the light usually emitted by the light-emitting element is emitted on the photosensitive element through the lens, and the circuit is maintained normally, if there is smoke blocking from it, the light that reaches the photosensitive element will be significantly weakened, so the photosensitive element converts the change of light intensity into a change of current, and sends an alarm signal through the amplification circuit; There is also a pipeline smoke detector, which generates a light-sensing current through the reflection or scattering of smoke, which is mainly used on ships.
Common photoelectric smoke fire detectors
How the emergency start and stop button works.
If the emergency start and stop button glass or the line is burned out, the signal relay of the emergency start and stop button loses power, and its normally closed point will start the water pump and transmit the alarm signal.
A common emergency start and stop button
How the deflation indicator works.
When a fire occurs in the protected area and the gas fire extinguishing system extinguishes the fire, the gas deflection indicator light will light up a red no-entry sign to warn people not to enter.
Common deflation indicators
How the terminal module works.
The terminal module uses the relay to switch the contact to output the voltage signal, and at the same time, the relay to switch the contact is used to feed back the startup signal to the input module.
Composition of a gas fire extinguishing control system
The gas fire extinguishing control system is composed of a gas fire extinguishing controller, a fire detector, an audible and visual alarm, an emergency start-stop button, a gas discharge indicator, heptafluoropropane, a terminal module, etc.;
How a gas fire extinguishing control system works
How a gas extinguishing controller works.
It can be equipped with smoke and temperature detectors, emergency start and stop buttons, sound and light alarms, gas release indicators and input and output modules, etc., with fire detection and gas fire extinguishing control functions, and can realize fire alarm and gas fire extinguishing control in one fire prevention zone.
Manual control: When the control mode selection button on the gas fire extinguishing controller is dialed to the "manual" position, the fire extinguishing system is in manual control state. When a fire occurs in the protection area, you can press the emergency start and stop button or the start button on the controller, and the fire extinguishing system can be started according to the prescribed procedure to release the fire extinguishing agent and extinguish the fire.
Automatic control: when the control mode selection key on the gas fire extinguishing controller is dialed to the "automatic" position, the fire extinguishing system is in an automatic control state, when a fire occurs in the protection area, the fire detector sends a fire signal, the gas fire extinguishing controller sends out a sound and light alarm signal, and at the same time issues a linkage instruction, closes the interlocking equipment, after a period of delay time, issues a fire extinguishing instruction, opens the solenoid valve to release the starting gas, and the starting gas opens the corresponding selection valve and container valve (bottle head valve) through the starting pipeline, and releases the fire extinguishing agent, Implement fire extinguishing.
Mechanical emergency manual operation: when a fire occurs in the protection area and the controller cannot issue a fire extinguishing instruction, the relevant personnel should be notified to evacuate the scene, close the linkage equipment, and then pull out the manual safety clip card on the starting valve of the corresponding starting bottle group, and press down the handle to open the starting valve, release the starting gas, and then open the selection valve, container valve (bottle head valve), release the fire extinguishing agent, and implement fire extinguishing. In this case, when the starting valve is repaired or the starting gas pressure in the starting cylinder is not enough to work, the selection valve handle of the corresponding fire extinguishing area should be opened first, the pressure arm should be opened, the selection valve should be opened, and then the manual handle on the container valve (bottle head valve) in the area should be opened to open the container valve (bottle head valve), release the fire extinguishing agent, and fire extinguishing should be implemented.