🔍 Key Concepts

• Engine protective devices that respond to low lubricating oil pressure • Difference between warning systems and shutdown or trip systems • Typical main diesel engine safety features found on merchant vessels

💭 Think About

• If lubricating oil pressure is lost, what is the most dangerous thing that could happen to the engine if it keeps running? • Which option describes something that directly protects the engine itself, rather than just alerting the crew? • On real ships/boats you’ve seen or studied, what actually happens first when lube oil pressure drops below a safe limit?

✅ Before You Answer

• Decide which option is specifically tied to main engine safety and protection, not general ship safety • Check which device is normally linked to engine control panels and shutdown circuits • Ask yourself: does this device act automatically on the engine, or mainly to notify people?