Fusable links are designed to separate at what degree?

• A. 180 degrees
• B. 360 degrees
• C. 90 degrees
• D. 45 degrees

Answer: (B)

Fusable links open when heat causes the fusible alloy inside to melt, separating the conductor and interrupting the circuit to protect equipment and limit fire spread. They’re rated to open at a specific temperature, and for shipboard protection that rating is 360 °F, meaning normal operation won’t trigger them but heat around a fire will cause them to separate. Lower temperatures would cause nuisance tripping or premature separation, so they aren’t used as the protection setting.