MRBF Terminal Fuse (Spare)

Description de l'article :

Spare part - Blue Sea MRBF Terminal Fuse, 100A to 300A

Buying a fresh install? The MRBF Fuse Kit is better value (block + fuse in your chosen rating for £36.99 inc VAT).

About this part

Blue Sea Systems Marine-Rated Battery Fuse, available in five ratings from 100A to 300A. Designed for use with the matching MRBF Terminal Fuse Block - never mount this fuse directly to a battery terminal.

• Ignition-protected (safe for installation aboard gasoline-powered boats)
• Clear window for visual blown-state indication
• Color-coded for amperage
• Satisfies ABYC requirements for DC main circuit protection

Choosing a rating

All five ratings share the same physical format, the same 58V DC voltage rating and the same interrupt capacity - only the amp rating (and body colour) changes. Every rating fits the same MRBF block.

• 300A - our default recommendation. Satisfies BS 7671's worst-case short-circuit requirement without nuisance-tripping on legitimate inrush (inverter startup, induction hobs, large DC-DC chargers).
• 100A-250A - choose a lower rating if you want the main fuse matched to your cable: pick the lowest rating that comfortably exceeds your maximum continuous system draw, and that does not exceed the continuous rating of your main positive cable.

Important: read before installing

Heads up. The 300A option is a short-circuit compliance fuse - not a cable-protection fuse.

At 300A the rating exists to satisfy BS 7671's worst-case short-circuit requirement without nuisance-tripping on legitimate inrush currents. It is not sized to protect any one cable or load downstream - so with a 300A fuse you remain responsible for either cabling rated for at least 300A continuous, or correctly-sized secondary fuses close to each load.

The lower ratings (100A-250A) let you bring the main fuse down to match your cable instead. A fuse holds 100% of its rating and tolerates brief surges well beyond it, so size to your continuous load - but check your inverter's startup surge against the rating before going tight.

For full sizing guidance see the MRBF Fuse Kit listing. If you're unsure, please ask before fitting.

Specifications

Technical reference

Drawings & curves sourced from Blue Sea Systems product documentation. Dimensions and trip curves apply to all ratings; trip currents scale with the nominal rating.