BS 5191 - Space-saving main fuse protection directly at the battery
The Blue Sea BS 5191 MRBF fuse block is arguably the most elegant and space-saving solution for protecting the main circuit. It is mounted directly onto the battery terminal (or a busbar), which completely eliminates the need for an additional connection cable between the battery and the fuse. It reliably protects currents up to 300 amperes.
Maximum protection in the smallest space
The block uses highly compact MRBF (Marine Rated Battery Fuse) fuses and, despite its minimal size, is completely ignition protected (ISO 8846). This means it can be safely installed in a battery box or engine compartment. A flexible insulating cap prevents short circuits in the event of accidental contact with tools.
Key advantages at a glance:
- Direct mounting: Can be mounted directly onto the 3/8" (M10) battery terminal.
- High current: Protects up to 300 amperes.
- Space-saving: Minimal space required in the battery compartment.
- Ignition protected: Complies with ISO 8846 for use in engine compartments.
- Corrosion protection: Tinned copper contacts for the marine environment.
Technical data (Blue Sea BS 5191):
| Property | Specification |
| Voltage range | Max. 58V DC |
| Fuse type | MRBF (Terminal Fuse) |
| Number of circuits | 1 |
| Max. current | 300 amperes |
| Mounting hole | M10 (3/8") |
| Ignition protection | ISO 8846 / SAE J1171 |
Note: MRBF fuses are sold separately.