Blue Sea 7650 Dual Circuit Battery System

Blue Sea 7650 — Solenoid / Dual Circuit Battery System

Automatic battery combiner that connects your starter battery to your house battery whenever the engine is running, so your alternator charges both. Disconnects when the engine stops to prevent your house loads from draining the starter battery.

Key Features

• 120A continuous, 500A momentary engagement capacity
• Automatic voltage-sensing — no manual switching, no user input required
• Manual override switch for emergency starting assist (combine batteries on demand)
• Integrated panel with status LEDs
• 12V or 24V systems

Why This Over a Plain VSR

A standard voltage-sensing relay only combines batteries. This system gives you manual override, integrated switching, and status indicators all in one unit. Cleaner install, fewer parts, more control.

Ideal For

• Van and RV dual-battery electrical systems
• Builds where you want alternator charging without a full DC-DC charger
• Budget-conscious alternative to Victron Cyrix / Orion on non-LiFePO4 bank configurations

Planning your alternator charging setup? Use our free System Build Helper to lay out your complete dual-battery wiring in minutes.