What is an overspeed trip and where is it implemented?

• A. A device that stops fuel or rotation if speed exceeds the limit; implemented in the engine control system.
• B. A device that starts the turbine when speed is too low.
• C. A safety device that prevents overheating.
• D. A manual switch for overspeed.

Answer: (A)

An overspeed trip is an automatic safety function that activates when the turbine’s rotational speed exceeds its maximum safe limit, stopping the engine to prevent damage. It works by cutting off fuel or otherwise halting rotation as soon as the excess speed is detected. This protection is implemented in the engine control system, which monitors speed with sensors and triggers the trip to enforce the limit. It isn’t about starting the turbine when speed is too low, nor is it simply a device to prevent overheating, and it isn’t a manual switch for overspeed—the action is automatic and fast to protect the machine.