BS 5031 - Maximum overview for installations in protected spaces

The Blue Sea BS 5031 fuse block from the proven ST series is aimed at professional boat builders, yacht owners, and motorhome outfitters who need to structure a large electrical system with up to 12 circuits. It is specifically designed for installation in enclosed and touch-protected environments – for example, directly behind a large switch panel or in a separate, moisture-protected distribution box. The solid, tinned copper bus bars and robust screw terminals ensure absolutely loss-free and vibration-proof power transmission.

The crucial difference: Blue Sea 5031 in comparison

Within the 12-circuit ST series, Blue Sea offers various configurations. The BS 5031 model is characterized by the clever combination of an integrated negative bus bar and the deliberate omission of a protective cover.

• Differentiation from the BS 5026 model: The 5026 model is the technically identical version (12 circuits, with negative bus), but is supplied including a transparent polycarbonate cover. The BS 5031 is the slimmer choice if the block is going to be hidden behind trim or a switch panel anyway, and a cover would only take up valuable installation depth.
• Differentiation from the BS 5032 model: The 5032 model also comes without a cover, but has no integrated negative bus bar. The BS 5031 offers the massive advantage here that both the positive and negative return lines of the 12 consumers can be centrally and tidily combined at a single block.

The advantages of the BS 5031: 

The base of the fuse block consists of flame-retardant, glass-fiber reinforced polycarbonate, which easily withstands high temperatures. To ensure maximum safety even in heavy seas or during vibrations while driving, all terminal screws (#8-32) for the consumer cables are equipped with captive star washers. This ensures that ring terminals remain permanently and securely fixed.

Advantages at a glance:

• For large projects: 12 individually fused circuits in one central location.
• All-in-one wiring: The integrated negative bus reduces cable clutter and simplifies ground return to the battery.
• Flat design: Without a cover, it is ideal for installations with limited mounting depth.
• High load capacity: 100 Ampere total load (max. 30 Amps per individual circuit).
• Marine-grade: Current-carrying components made of tinned copper offer maximum protection against corrosion.

Technical Data (Blue Sea BS 5031):

Note: ATO/ATC blade fuses are not included and must be ordered separately to match your consumers.