Collection: Fuses

Marine fuses to protect onboard circuits

A fuse primarily protects the cable and circuit against overcurrents. It must be selected based on cable cross-section, length, voltage, rated current, inrush current, and fuse holder location. On a boat, the correct choice limits overheating, simplifies diagnostics, and prevents an electrical fault from becoming a safety hazard.

Blade fuses and auxiliary circuits

ATO/ATC blade fuses protect small to medium circuits: lighting, electronics, auxiliary pumps, instruments, or service outlets. ATO/ATC fuses cover these common uses, while the easyID 5 A fuse and the easyID fuse kit make it easier to identify a blown fuse. To centralize multiple circuits, ST Blade waterproof fuse blocks, compact ST Blade fuse blocks, ST Blade fuse blocks with cover, or the ST Blade fuse block on battery terminal neatly organize blade circuits.

AMI/MIDI, MEGA/AMG, and ANL for high power

High-power circuits require fuses suitable for higher currents: chargers, inverters, windlasses, thrusters, alternators, or distribution circuits. AMI/MIDI fuses cover compact medium-power protection, MEGA/AMG fuses are designed for stronger circuits, and ANL fuses are commonly used on battery and distribution circuits. Fuse holders such as the ANL fuse holder with cover, the ANL fuse block with insulating cover - 35 to 750 A, the MEGA AMG 100–300 A fuse holder with cover, or the ANL through-panel 500 A fuse holder ensure proper contact and mechanical protection of the fuse.

MRBF and Class T near batteries

MRBF fuses are installed directly or very close to battery terminals to quickly protect a main circuit. MRBF terminal fuses can be paired with holders like the surface-mount MRBF fuse blocks, the surface-mount MRBF fuse block - common source, the dual MRBF terminal fuse block - 30 to 300 A, or the MRBF terminal fuse block - 30 to 300 A. For very high-current installations or where high breaking capacity is required, Class T fuses and the Class T fuse block with insulating cover - 225 to 400 A meet battery, inverter, and main distribution requirements.

Victron fuses and accessories

Victron installations often use MEGA fuses in DC enclosures and wiring. The modular MEGA fuse holder and the 60 A MEGA fuse complement protections around chargers, inverters, batteries, and DC bus when the configuration requires this format.

Properly sizing a protection

The rating is not chosen solely based on the connected device: it must also protect the cable. Verify cross-section, length, continuous current, startup surges, temperature, breaking capacity, and fuse holder type. To build a complete circuit, also see the Circuit breakers, Electrical panels, Electrical wiring, Terminals, Battery cutoffs, Distribution, and Electrical collections.