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

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

The Arco Marine BI-1203-3A is an inboard/outboard battery isolator that can handle 1 alternator, 3 batteries, and 120A max. Rated for use with 10 to 350-amp alternators on 12, 24, or 32-volt negative ground systems.

*Includes exciter terminal

Features:

• 1 alternator, 3 batteries, 120A max
• Inboard and outboard battery isolators are solid-state devices that allow electrical current to flow in one direction ONLY, thus permitting the alternator to be connected directly to two batteries without fear of one higher-charged battery discharging into the lower-charged battery.
• Both batteries are always being charged automatically, in proportion, to their needs whenever the engine is running.
• When battery isolators are used in conjunction with selector switches, it is not necessary to change the switch position to provide for charging of both batteries.
• Isolators provide proportioning of the output or charging current on the alternator to the batteries as required, regardless of switch position.

NOTE: Battery Isolators cannot be used on 12 volt charging systems with 24 volt trolling motors or newer outboard engines with rectifier-regulator charging systems.

The ARCO Marine BI-1203-3A battery isolator is designed to efficiently manage multiple batteries in marine and RV applications. Capable of handling up to 120 amps, this solid-state inboard/outboard isolator allows for the seamless charging of three batteries from a single alternator, ensuring reliable power distribution across your system. It is compatible with 10 to 350-amp alternators on 12, 24, or 32-volt negative ground systems, making it versatile for various vessel configurations. The unit includes an exciter terminal for easy installation and optimal performance.

Built for durability and dependable operation, the BI-1203-3A features one alternator and three batteries, automatically charging each in proportion to their needs while the engine runs. Its solid-state design ensures that current flows in only one direction, preventing higher-charged batteries from discharging into lower-charged ones, thus protecting your power system. When used with selector switches, it eliminates the need to manually change switch positions to charge both batteries, simplifying maintenance and operation. The isolator also provides consistent current distribution, maintaining balanced charge levels regardless of switch settings.

Designed specifically for marine and other 12-, 24-, or 32-volt negative ground systems, this battery isolator is essential for boat owners seeking to optimize battery management. It ensures both batteries are charged automatically and proportionally, helping extend battery life and improve system reliability. Please note that this isolator is not suitable for 24-volt trolling motors or newer outboard engines with rectifier-regulator charging systems. Proper installation and use will provide years of maintenance-free operation, supporting your vessel's electrical needs efficiently and safely.

Features:

• Capable of handling 120 amps with 1 alternator and 3 batteries

• Solid-state inboard/outboard battery isolator with unidirectional current flow

• Includes exciter terminal for simplified installation

• Automatically charges batteries in proportion to their needs when engine runs

• Compatible with 12, 24, or 32-volt negative ground systems

• Eliminates the need to change switch positions when used with selector switches

• Provides consistent current distribution regardless of switch settings

• Designed for marine and RV electrical systems, not suitable for 24-volt trolling motors or outboard rectifier systems