Which action best describes the role of interlocks and safety relays?

• A. Prevent unsafe operation by ensuring conditions are met before actuation and provide fault indication.
• B. Increase electrical noise.
• C. Provide decorative lighting.
• D. Record flight data for later analysis.

Answer: (A)

Interlocks and safety relays act as gatekeepers in the control system. They ensure that all safety conditions are satisfied before an actuator can be energized, such as safeties being in place, guards closed, and sensors confirming a safe state. If any condition isn’t met or a fault appears in the safety circuits, the interlock or safety relay trips, blocking actuation and often signaling a fault. This protects personnel and equipment by preventing hazardous movements and providing a fault indication so issues can be addressed. The other options don’t fit this protective, gating role: they don’t create electrical noise, aren’t used for decorative lighting, and don’t record flight data.