Analog addressable devices are individually identified with an address (number) on a loop of wiring. The control panel communicates with each device in turn and each device reports back with an analog value based upon how much smoke or heat is present. The control panel, not the detector, then makes the decision to sound the alarm system.
With an intelligent system, if a fire is detected, its position can be pin-pointed because each device has its own unique address which means its exact location can be found quickly.
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