ARCO Marine BI-1203-3A Battery Isolator - 120A - 1 Alternator, 3 Battery

The Arco Marine BI-1203-3A Battery Isolator is an essential component for marine enthusiasts seeking reliable power management on their vessels. Designed to efficiently handle multiple batteries and alternators, this isolator ensures your electrical system operates smoothly and safely.

Product Overview

The BI-1203-3A Battery Isolator is a high-performance inboard/outboard device tailored for marine applications. Capable of managing one alternator and three batteries with a maximum current of 120A, it is compatible with 12, 24, and 32-volt negative ground systems. Whether you have a single alternator or multiple power sources, this isolator ensures optimal battery charging and protection.

Key Specifications

Feature	Specification
Maximum Current	120A
Alternators Supported	1 (10 to 350 Amp)
Battery Capacity	3 Batteries
Voltage Compatibility	12V, 24V, 32V Negative Ground Systems
Additional Features	Includes Exciter Terminal

Features and Benefits

• One Alternator, Three Batteries, 120A Maximum: Efficiently manages power distribution from a single alternator to up to three batteries, ensuring balanced charging and optimal performance.
• Solid-State Isolation: Prevents reverse current flow, safeguarding your batteries from discharging into each other and extending their lifespan.
• Automatic Proportional Charging: Batteries are charged in proportion to their individual needs whenever the engine is running, ensuring each battery receives the appropriate charge.
• Seamless Integration with Selector Switches: Eliminates the need to manually switch positions to charge multiple batteries, providing a hassle-free user experience.
• Proportioned Output Regardless of Switch Position: Maintains balanced charging distribution even when selector switches are in different positions, ensuring consistent battery performance.

How It Works

The BI-1203-3A utilizes solid-state technology to allow electrical current to flow in only one direction. This ensures that when your engine is running, the alternator can charge all connected batteries without the risk of a higher-charged battery draining into a lower-charged one. The exciter terminal included in the package facilitates seamless integration with your vessel’s electrical system, promoting efficient and reliable power management.

Important Notes

Compatibility Warning: This battery isolator is not suitable for use with 12-volt charging systems equipped with 24-volt trolling motors or newer outboard engines that feature rectifier-regulator charging systems. Ensure your system aligns with the specified voltage requirements before installation.

Return Policy

This product may not be returned to the original point of purchase. Please contact the manufacturer directly with any issues or concerns.

Additional Resources

Download the Quick Guide (PDF)

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We currently ship to the Contiguous 48 States.

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