A fusible link(s) is a protective device used in an electrical circuit. When current increases beyond a certain amperage, the fusible metal wire of the link melts, thus breaking the electrical circuit and preventing further damage to the other components and wiring. Whenever a fusible link is melted because of a short circuit, correct the cause before installing a new link. All fusible links are the plug-in kind. To replace them, simply unplug the bad link and insert the new one.