Blue Sea Systems BatteryLink Battery Charger, 2 Bank, 12V, Integrated ACR

Overview

The Blue Sea Systems BatteryLink Charger is a 12V DC, two-bank marine battery charger range for boats that need charging at the dock and charge sharing while underway. It combines a multistage AC battery charger with an integrated Automatic Charging Relay, so two isolated battery banks can be charged from shore power and the alternator can help charge both the Start and Auxiliary batteries away from the dock.

This North America version uses a NEMA 5-15P plug for standard shore power connections and supports AGM, flooded, and TPPL battery types. Both amperage options use 1 negative and 2 positive output connections, a typical 13.5V DC float voltage, battery temperature compensation, start isolation for sensitive electronics, and an LED remote indicator for charge status at the helm.

The range is built for real marine electrical layouts where battery banks need to stay isolated during normal use but still receive charge from available sources. It fits well on cruising boats, fishing boats, and small workboats with separate starting and house or auxiliary battery banks.

Key features

• Charges two isolated 12V battery banks from AC shore power using a 3-stage charging profile.
• Shares alternator charging with both Start and Auxiliary batteries through the integrated ACR when away from the dock.
• Available in 10A and 20A charging configurations to match different battery bank sizes and onboard loads.
• Battery temperature compensation adjusts charging behavior as battery temperature changes, helping reduce overcharging and undercharging risk.
• Start isolation helps protect sensitive onboard electronics from voltage sags and spikes during engine starting.
• North American NEMA 5-15P plug and 50/60 Hz AC input support for dockside charging.
• Compatible with AGM, flooded, and TPPL batteries.
• IP67 rating, ignition protection, and compliance with ABYC A-31, ISO 8846, SAE J1171, UL 1236, CSA C22.2 No. 107.2-01, and FCC Part 15 Subpart B.

Variants

This BatteryLink Charger is offered in two amperage configurations for North American installations.

The main differences are charging output and ACR rating. Both versions are 12V DC two-bank chargers with shore power charging, alternator charge sharing, temperature compensation, start isolation, an LED remote indicator, and a North American plug.

• 7605: 10A amperage. This version uses a 10A multistage charger with a 65A continuous ACR, making it a practical fit for smaller two-bank systems with start and auxiliary batteries.
• 7608: 20A amperage. This version uses a 20A multistage charger with a 170A continuous ACR and adds remote emergency parallel for combining batteries if the start battery is low.

Electrical and system integration

The charger is meant for 12V DC battery systems with separate Start and Auxiliary banks. At the dock, shore power charges the banks through the onboard AC charger. Underway, the ACR shares alternator charge with both banks while still supporting battery isolation when charging voltage is not present.

The 10A version uses a universal 90-265V AC input, while the 20A version uses a 100-240V AC input. Both operate at 50/60 Hz and use a typical float voltage of 13.5V DC. The 20A version also lists a typical absorption voltage of 14.4V DC.

Installation and fit

The unit should be installed as part of a properly protected marine battery charging system, with cable size, terminal torque, battery capacity, and overcurrent protection matched to the selected model. The 10A version uses 1/4-inch-20 terminal studs with 60 in-lb torque, while the 20A version uses a 1/4-inch negative terminal stud at 60 in-lb and 3/8-inch positive terminal studs at 140 in-lb.

For battery sizing, the 10A version is listed for 60Ah minimum and 120Ah maximum battery bank sizes. The 20A version is listed for 100Ah minimum per bank and 400Ah maximum total capacity across both banks. These limits make the amperage choice important when replacing an existing charger or planning a new two-bank system.

Use cases on board

This charger range suits boats that spend time both at the dock and underway, especially where a start battery and a house or auxiliary battery need managed charging without tying the banks together all the time. It is a strong match for helm-accessible charge status monitoring, weekend cruising, fishing electronics, cabin loads, and small vessel battery systems that benefit from automatic charge sharing.

What's included

• Submersible temperature sensor