🔍 Key Concepts

• Review how this alternator is normally cooled using a closed air system with a heat exchanger that depends on cooling water. • Consider what happens to internal temperature when you lose water to the heat exchanger, and how opening the emergency air inlet panel and outlet doors changes the cooling path. • Think about the relationship between ventilation/airflow and allowable electrical load on a generator when its main cooling system is degraded.

💭 Think About

• Based on figure A, trace the normal airflow path through the stator core and heat exchanger. If the heat exchanger no longer has cooling water, how effective is that closed path? • If you switch to emergency ventilation by opening or closing panels and doors, will the alternator be better or worse cooled than in the normal mode with no water flow? How should that affect maximum safe load? • Which answer choices are clearly unsafe because they either forbid operation needed in an emergency or assume full-rated cooling when an important cooling source has been lost?

✅ Before You Answer

• Identify whether the emergency air inlet panel and outlet doors are intended to INCREASE or DECREASE cooling airflow when water cooling is lost. • Decide whether running at full rated load without the designed cooling system would be realistic for a large enclosed alternator. • Eliminate any option that implies running the alternator with no effective cooling (no water and no additional air path).