The exact design of a commercial fire alarm system is determined by the commercial space’s occupancy classification and the local codes mandated by the Authority Having Jurisdiction (AHJ) for that specific occupancy classification. But regardless of the system design, all commercial fire alarm systems must have a Fire Alarm Control Panel (FACP).
An FACP is the “brain” of the fire alarm system to which all other devices are connected. When an initiating device (such as a smoke detector or a manual pull station) transmits an alarm signal to the FACP, it activates the notification devices to alert the occupants via audible and visual alarm devices.
An FACP also has a digital display that provides the current status of the fire alarm system. In modern “addressable” fire alarm systems, every device connected to the FACP has a unique address (for example: “57 - smoke detector basement electrical room”) which allows the FACP to display the specific device that initiated the signal. This level of detail allows the authorized personnel to quickly locate the source of the alarm. The building’s authorized personnel also use the FACP’s functional switches to acknowledge signals, silence alarms and reset the system once the alarm condition has been cleared by fire department personnel.
The three main types of signals received by the FACP are Alarm, Supervisory and Trouble. Here are the brief descriptions of each of the signal type:
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