Conventional Control Panel
In typical design of conventional re alarm system, the detectors are wired as a circuit or zone which send signal re conditions to a control panel by changing from a high to low impedance. The panel shall detects this impedance change by current monitoring and identi es the alarm zone. However, Individual detectors cannot be identi ed.
Conventional panels have been around ever since electronics became small enough to make them viable. Conventional panels are used less frequently in large buildings than in the past, but are not uncommon on smaller projects such as small schools, stores, restaurants, and apartments.
A conventional Fire Alarm Control Panel employs one or more circuits, connected to sensors (initiating devices) wired in parallel. These sensors are devised to dramatically decrease the circuit resistance when the environmental in uence on any sensor exceeds a predetermined threshold. In a conventional re alarm system, the information density is limited to the number of such circuits used.
To facilitate location and control of re within a building, the structure is subdivided into de nite areas or zones. Floors of a multi- story building are one type of zone boundary.
An Initiating Device Circuit connected to multiple devices within the same “zone” of protection, effectively provides 2 bits of information about the zone to the state of the circuit; normal, or off normal and alarm or quiescent. The state of each Initiating Device Circuit within a zone displays at the Fire Alarm Control Panel using visible indications called Annunciators. These Annunciators may employ a graphical representation of the Zone boundaries on a oor plan (Zone map) using textual descriptions, illuminated icons, illuminated sections, or illuminated points on the map corresponding to Initiating Circuits connected to the Fire Alarm Control Panel.