Originally Posted by Hulk
Pardon my ignorance: why do I need this? It's a fuse for the fuse box?
Fuses, fusible links and circuit breakers protect your wire should the insulation fail because the combined load exceeds the conductor's rating or a short. No matter how it happens, if the feed conductor is asked to carry more current than it's capable, it heats up. Heat causes fires. If you used a fuse or breaker that is also fine, fusible links are convenient because they are usually easier to work with in tight spots. Their downside is they only work once and might be a bit more PITA to fix compared to pushing reset or replacing a fuse.