Blue Sea 5118 250AMP Class T Fuse

The Blue Sea 5118 250AMP Class T Fuse is a critical electrical protection component engineered for demanding marine, RV, automotive, and industrial DC power systems. This high-capacity fuse protects valuable equipment and circuits from catastrophic damage caused by short circuits and dangerous current overloads. Professionals and experienced users rely on Class T fuses when standard cartridge fuses prove inadequate for high-amperage applications requiring split-second response times.

The 5118 delivers an impressive 20,000 Ampere Interrupt Capacity (AIC), meaning it safely interrupts fault currents up to that threshold without violent failure or arc continuation. Its Class T construction uses a silver-alloy element that responds with extreme speed to short-circuit events—typically in milliseconds—protecting downstream components before damage occurs. UL certification to standard 248-15 confirms compliance with rigorous safety requirements, while DC testing to UL standard 198L ensures reliable performance in DC-dominant systems common in marine and renewable energy applications. The compact 4 x 2 x 6 inch form factor makes installation straightforward in panel-mount or fuse-holder configurations.

This 250-amp fuse is ideal for users protecting high-draw circuits such as battery banks, inverter systems, thruster motors, and auxiliary power distribution in marine vessels and recreational vehicles. It pairs seamlessly with Blue Sea Systems fuse blocks and holders designed for Class T cartridges. Installation requires a compatible Class T fuse holder rated for 250 amps; the fuse itself weighs only 0.3 lbs and occupies minimal panel space, making retrofits practical even in compact electrical enclosures. Verify your fuse holder accepts Class T cartridges before purchase to ensure proper fit and electrical safety.