Non-resettable fuses are single-use circuit protection devices that break a circuit when a fault is detected, offering protection to vital components. This type of fuse is designed to be mounted directly onto a printed circuit board (PCB). This type of fuse is for single use, with the fuse body and two wires that extend outside the body.

How do non-resettable fuses work?

Non-resettable fuses perform the role of a simple circuit breaker in a circuit. When a fault such as overcurrent or a short circuit is detected, the metal strip inside the fuse melts, stopping the flow of current and preventing damage to the circuit and any other connected devices. Once the fuse has blown, it must be replaced as it is non-resettable.

These fuse types are often used in motors, where if overheating occurs, the power is cut before any permanent component damage occurs.

Types of non-resettable fuses

Non-resettable fuses can differ by their voltage and current rating, their size and their level of resistance, measured in ohms. Their body material can also vary widely, from thermoplastic to glass ceramic. This type of fuse can have a range of maximum and minimum operating temperatures.