Blue Sea Systems Mini Add-A-Battery Kit 65A Dual-Circuit — Compact Marine ACR with Tin-Plated Studs

The Blue Sea Systems Mini Add‑A‑Battery Kit 65A (model 7649) is a compact, marine‑rated dual battery management system that automatically combines charging and isolates batteries to protect your starter and house banks.

This small, purpose-built kit provides automatic battery control for small boats and installations where space is limited. It pairs a mini dual‑circuit battery switch with an automatic charging relay (ACR) rated for 65 amps, simplifying wiring while ensuring both batteries receive charging current when the engine or charger is active, and preventing starter battery drain when systems are off.

How does the kit manage charging without extra switches?

The built‑in Automatic Charging Relay senses system voltage and automatically connects both batteries during charging events. When charging stops and voltage drops, the relay opens to isolate the banks, reducing the risk of the starter battery becoming unintentionally discharged.

• Automatic Charging Relay combines batteries only while voltage indicates charging.
• Automatic isolation when the system is at rest to protect starter bank.
• Eliminates the need for manual switch operation during routine charging.

What makes the Mini Dual Circuit Plus switch suitable for small boats?

The Mini Dual Circuit Plus switch separates the starter and house banks while offering compact, straightforward controls tailored to limited helm or battery compartment space. It reduces wiring clutter by providing a single integrated unit for two‑bank systems and includes an emergency combine function for occasional parallel starting assistance.

• Compact footprint designed for tight installations and small craft.
• Independent starter and house bank control for cleaner electrical layouts.
• Emergency combine feature to link batteries temporarily if starting assistance is required.

Is this kit durable enough for marine environments?

Yes — the kit uses marine‑rated components and tin‑plated copper studs to resist corrosion and maintain reliable connections in wet, salty conditions. The design focuses on long‑term reliability for small outboard and inboard applications with a continuous 65 A rating appropriate for many compact charging systems.

• Tin plated copper studs for improved corrosion resistance and conductivity.
• Marine‑grade materials selected to withstand boating environments.
• Continuous 65 A rating suitable for many small charging sources.

How will installation affect my wiring and maintenance?

The Mini Add‑A‑Battery kit simplifies two‑bank wiring by integrating switching and charging relay functions into a single assembly, reducing terminal count and routing. Because the relay engages automatically, routine operation requires minimal user intervention and lowers chances of human error during charging cycles.

• Consolidates switching and charging relay to reduce wiring complexity.
• Fewer external controls to operate during normal use.
• Clear terminals and robust studs simplify service and inspection.

Who is this for: The Blue Sea Systems 7649 Mini Add‑A‑Battery Kit is ideal for owners of small boats, tenders, and compact vessels who need reliable starter/house bank management without sacrificing space. It suits DIY installers, boat builders, and anyone replacing inefficient or bulky switching systems with a marine‑rated, automatic solution that balances protection, convenience, and corrosion resistance.