What does the fault isolation feature do in an addressable fire alarm system?

• A. It prevents any signaling during fault.
• B. It isolates a faulty device or segment to prevent the fault from affecting the entire system.
• C. It increases sensitivity.
• D. It shuts down the system.

Answer: (B)

Fault isolation in an addressable fire alarm system means the control panel identifies a fault on a specific device or a section of wiring and effectively disconnects that part from the signaling loop. This containment prevents that fault from dragging down the entire system, so all other devices continue to monitor, report, and respond as needed. It also gives technicians a clear location to fix, reducing downtime and avoiding unnecessary shutdowns of the whole system. It doesn’t stop all signaling during a fault—only the faulty portion is isolated—nor does it increase detector sensitivity or shut the system down entirely.