What are surveillance tests and what do they verify?

• A. Increase data throughput
• B. Detect channel faults and verify ongoing fault-detection effectiveness
• C. Calibrate sensors
• D. Train operators

Answer: (B)

Surveillance tests focus on the protection channels’ ability to detect faults and keep that fault-detection capability working over time. They verify that if a fault occurs in a channel—due to sensor drift, wiring degradation, or electronic failure—the fault-detection logic will notice it and trigger the appropriate response. In practice, these tests may involve injecting test faults or monitoring channel behavior to confirm that alarms and protective actions would occur when needed, as well as that the fault-detection system remains effective between tests. They aren’t about increasing data throughput, calibrating sensors, or training operators.