Blue Sea Systems 7650 Add-A-Battery Kit, 120 Amp Dual Circuit System with Automatic Charging Relay

The Blue Sea Systems 7650 Add-A-Battery Kit is a complete battery management system for boats running two battery banks. Rated for a continuous 120 Amps, it is built for inboards and larger outboards and simplifies switching and charging without requiring external regulators or isolators. At the core of the kit is a Dual Circuit Plus battery switch that manages the starter and house banks independently while still allowing simple single ON and OFF operation for everyday use. An integrated Automatic Charging Relay senses charging voltage and automatically combines both batteries during engine operation so each bank receives a charge, then isolates the batteries again once charging stops and voltage drops, helping protect sensitive electronics and preserve starting power. For situations where one battery bank is discharged, the kit includes an emergency parallel combine function that links both banks together to support engine starting. Electrical connections use stud-type terminals with copper contacts, and the current-carrying studs are tin plated to resist corrosion in harsh marine environments, supporting long-term reliable conductivity. The 7650 is designed to reduce wiring complexity and switching errors compared to running two separate battery banks with manual switches.

Specifications

• Brand: Blue Sea Systems
• Manufacturer Part Number: 7650
• Category: Marine Battery Charger Accessories
• Current Rating: 120 Amps
• Wattage: 1440 watts
• Connector Type: Stud
• Contact Material: Copper
• Contact Type: Normally Open
• Mounting Type: Panel Mount
• Operation Mode: Automatic
• Lower Temperature Rating: 55 Degrees Celsius
• Upper Temperature Rating: 85 Degrees Celsius
• Specification Met: ETL, IP54
• UPC: 632085076504
• Weight: 2.36 pounds

Frequently Asked Questions

What does the Blue Sea Systems 7650 Add-A-Battery Kit do? The Blue Sea Systems 7650 is a 120 Amp dual circuit battery management system that lets a boat charge and manage two battery banks with a single Dual Circuit Plus switch and an integrated Automatic Charging Relay.

Does the 7650 kit include a battery isolator or external regulator? No separate external regulator or isolator is needed. The 7650 kit's built-in Automatic Charging Relay combines the batteries during charging and isolates them at rest, handling that function internally.

What is the current rating of the Blue Sea Systems 7650? The 7650 Add-A-Battery Kit carries a continuous current rating of 120 Amps (1440 watts), suitable for inboards and larger outboards.

How does the switch in the 7650 kit work day to day? The kit's Dual Circuit Plus battery switch manages the starter and house banks independently but is operated with a single ON and OFF control, reducing the switching errors that come with running two separate manual switches.

What happens if one battery bank is dead and I need to start the engine? The 7650 includes an emergency parallel combine function that links both battery banks together, allowing the healthy bank to help start the engine if the other bank is discharged.

What are the terminals made of on the 7650 kit? The 7650 Add-A-Battery Kit uses stud-type terminals with copper contacts, and the current-carrying studs are tin plated to resist corrosion in a marine environment.

How much does the Blue Sea Systems 7650 weigh? The Blue Sea Systems 7650 Add-A-Battery Kit weighs 2.36 pounds.

What temperature range is the 7650 rated for? The 7650 is rated from 55 degrees Celsius on the low end to 85 degrees Celsius on the high end.

Is the 7650 kit certified to any standards? Yes, the Blue Sea Systems 7650 meets ETL and IP54 specifications.

Is the 7650 kit automatic or does it require manual battery combining? Operation is automatic: the Automatic Charging Relay in the 7650 senses charging voltage and combines or isolates the two battery banks on its own, with manual combine only needed for the emergency parallel function.

What is the UPC for the Blue Sea Systems 7650? The UPC for the Blue Sea Systems 7650 Add-A-Battery Kit is 632085076504.

How is the 7650 mounted? The Blue Sea Systems 7650 uses a panel mount configuration.