What is the maximum temperature rating for fusible links?

• A. 140-150 F
• B. 155-165 F
• C. 170-180 F
• D. 190-200 F

Answer: (B)

Fusible links act as temperature-triggered shutoffs: they are designed to melt and open the circuit when heat reaches a defined level, preventing overheating or fire propagation in the system. The maximum temperature rating tells you the highest ambient temperature at which the link is expected to stay intact and still behave reliably when heat continues to rise. The 155-165 °F range is chosen because it provides a safe balance: it tolerates normal storage and equipment heat, but will reliably melt and interrupt the circuit as temperatures approach hazardous levels. That’s why the standard maximum rating for these links is around 155-165 °F.