Which statement correctly describes the role of a starter-generator during engine operation?

Which statement correctly describes the role of a starter-generator during engine operation?

• A. It begins as a starter to start the engine and automatically shifts to generation mode when the engine is running.
• B. It only operates as a starter and never generates electricity.
• C. It operates as an alternator only when the engine is off.
• D. It disconnects during normal operation.

Answer: (A)

The key idea is that a starter-generator is a single unit that handles two roles: first, it acts as a motor to crank the engine, and once the engine reaches operating speed, it automatically shifts into generator mode to supply electrical power and charge the battery. This automatic transition lets the system start the engine and then immediately begin generating electricity without a separate generator. It remains connected and supplying power during normal operation. It does not operate only as a starter, nor does it generate only when the engine is off, nor does it disconnect during operation.

The key idea is that a starter-generator is a single unit that handles two roles: first, it acts as a motor to crank the engine, and once the engine reaches operating speed, it automatically shifts into generator mode to supply electrical power and charge the battery. This automatic transition lets the system start the engine and then immediately begin generating electricity without a separate generator. It remains connected and supplying power during normal operation. It does not operate only as a starter, nor does it generate only when the engine is off, nor does it disconnect during operation.