🔍 Key Concepts

• Reverse power flow in an AC generator running in parallel with others • What happens when a generator stops driving and starts being driven as a motor • Protection functions found on a ship’s generator circuit breaker

💭 Think About

• Think about the direction of power flow: from generator to bus, or from bus back into the machine—what would be dangerous in that second case? • If a prime mover (diesel/turbine) loses fuel or power while still synchronized, what could happen to the alternator without reverse power protection? • Which of the options describes a problem that specifically involves power flowing in the opposite direction through a generator?

✅ Before You Answer

• Identify which choice relates directly to power flowing from the switchboard into the generator instead of the other way around • Rule out any options that mainly deal with voltage level or overcurrent—those are usually separate protective functions • Ask yourself: which option describes protecting the machine from being driven as a motor rather than acting as a generator?