Fire Detection systemSystem
A fire alarm system has a number of devices working together to detect and warn people through visual and audio appliances when smoke, fire, carbon monoxide or other emergencies are present.
These alarms may be activated automatically from smoke detectors and heat detectors or may also be activated via manual fire alarm activation devices such as manual call points or pull stations.
Alarms can be either motorized bells or wall mountable sounders or horns. They can also be speaker strobes which sound an alarm, followed by a voice evacuation message which warns people inside the building not to use the elevators.
Basic Components of Fire Alarm Control System
Fire Alarm Control Panel
Fire Alarm Control PanelPanel
The brains of the system
Provides power to the system, monitors inputs and controls outputs through various circuits.
Performs other functions as required by the appropriate code.
Addressable Fire Alarm System
Every device connected to the addressable system has its own unique address. When a fire is detected, the device’s address shows up on the main control panel, telling us exactly which device has been activated. This will enable us to find the exact location of a fire and extinguish it quickly.
1. Each device (detector, pull station…) has a unique number assigned to it called the address for reporting alarms and troubles.
2. Employs a Signaling Line Circuit (SLC) Loop along which all addressable input and output devices are connected to the fire alarm control panel.
3. Addressable devices transmit an electronic message back to the Control Unit representing their state (Normal, Alarm, Trouble) when polled by the Control Unit.
Conventional Fire Alarm System
With a conventional system, there is no way of pinpointing the exact location of the fire. By wiring your building into different zones, one can get a general idea of where the fire is. For instance, if you have two floors, you could wire the first as ‘zone and the second as zone 2. So, if a fire occurs in zone 1, you know that the fire is somewhere on the first floor.
1) The simplest type of control unit. Generally, a single circuit board contains a power supply, control, initiating and notification circuitry.
2) Some models use auxiliary circuit boards to perform special functions.
3) Input/output devices connect to dedicated circuits.
4) Designated outputs occur when initiating signals are received.
Limited special functions and capabilities.
A fire alarm system can have a variety of input devices. We divide it into two parts, one is Initiating Device and one is Initiating Device Circuit (IDC). A system component that originates transmission of a change of state condition, such as a smoke detector, manual fire alarm box, supervisory switch, etc is known as Initiating Device. A circuit to which automatic or manual initiating devices are connected where the signal received does not identify the individual device operated is known as a Initiating Device Circuit (IDC)
A fire alarm system can have a variety of output devices. We divide it into two pans, one is Notification Appliance and one is Notification Appliance Circuit. Notification Appliance is a fire alarm system component such as a bell, horn, speaker. light, or text display that provides an audible, tactile, or visible output, or any combination thereof. Notification Appliance Circuit is a circuit or path directly connected to a notification appliance.