A traditional fuse will break open and does not recover after the fault event is corrected. The fuse component has to be replaced for the circuit to function again.
A PTC fuse is a special fuse that will reset after power is removed from the circuit. It is a temperature-dependent resistor or thermistor whose resistance rises with increasing temperature.
A PTC fuse quickly increases its resistance as a response to an overcurrent, over-temperature, or short circuit situation to restrict the current flow. PTCs enable the equipment to function, with extreme cases the exception. Circuit designers select PTCs on occasions where maintaining user transparency, or constant system uptime is at a premium.
Poll Question: Are You Specifying PTC Resettable Fuses in Your Next Electronic Design?