How does a fault isolation device improve system reliability?

• A. It isolates the faulted device or segment to allow the rest of the system to operate while the fault is addressed.
• B. It automatically repairs faults.
• C. It increases the number of detectors.
• D. It reduces power consumption.

Answer: (A)

Fault isolation devices improve system reliability by containing faults within a small part of the network so the rest of the system can keep operating while the fault is addressed. When a fault occurs, the isolation mechanism separates the faulty device or segment, preventing the problem from spreading and causing a broader failure. This keeps critical alarms and functions active, reduces downtime, and makes maintenance faster because responders can see exactly where the issue is.

Automatic repairs, more detectors, or lower power use aren’t the primary purpose of fault isolation. It’s about stopping the fault from taking down the whole system and allowing continued operation and quicker troubleshooting.