Which component in heat-producing appliances melts a pellet to turn off the unit when overheated?

Which component in heat-producing appliances melts a pellet to turn off the unit when overheated?

• A. Thermal Switch
• B. Thermal Cutoff
• C. Thermal Fuse
• D. Circuit Breaker

Answer: (B)

Temperature-triggered, one-time shutdown protection in heat-producing appliances interrupts power when the internal temperature exceeds a safe limit. The component that melts a small fusible pellet to open the circuit and stop the unit when it overheats is a thermal cutoff. Once the pellet melts, the circuit is permanently opened, and the device must be replaced. This behavior makes it a non-resettable safety device, unlike a thermal switch which resets after cooling, or a circuit breaker which protects primarily against overcurrent.

Temperature-triggered, one-time shutdown protection in heat-producing appliances interrupts power when the internal temperature exceeds a safe limit. The component that melts a small fusible pellet to open the circuit and stop the unit when it overheats is a thermal cutoff. Once the pellet melts, the circuit is permanently opened, and the device must be replaced. This behavior makes it a non-resettable safety device, unlike a thermal switch which resets after cooling, or a circuit breaker which protects primarily against overcurrent.