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Arco Starting & Charging BI-1203-3A Battery Isolator 120A 1 Alternator 3 Battery

Manufacturer

Arco Starting & Charging

<h3>Nearly Six Decades of Marine Electrical Excellence</h3><p>ARCO Starting & Charging has been the trusted name in marine electrical components for nearly 60 years, setting the gold standard for OEM-quality replacement parts. Operating from their Florida facility, ARCO manufactures, tests, and warehouses every component in the USA, ensuring rigorous quality control before any part leaves their 100,000-square-foot production center. What sets ARCO apart from competitors is their commitment to testing every unit beyond normal operating conditions, using state-of-the-art computerized assembly lines and automated digital load testers to verify performance specifications.</p><p>The company's dedication to proven dependability has earned them a reputation among marine mechanics, boat owners, and commercial operators who demand reliability in challenging saltwater environments. ARCO products consistently meet or exceed OEM specifications, backed by their comprehensive warranty program that demonstrates confidence in their manufacturing processes. Their engineering team comprises industry veterans with decades of experience in rotating electrical components, providing technical expertise that translates into innovative product solutions.</p><h3>Comprehensive Marine Starting & Charging Solutions</h3><p>ARCO's product lineup addresses every aspect of marine electrical systems. Their <a href="/7236-arco-starting-charging-tilttrim-motors-201071">tilt/trim motors</a> deliver precise control for outboard and stern drive positioning, featuring corrosion-resistant construction and reliable performance in harsh marine conditions. The company's <a href="/7236-arco-starting-charging-starters-inboard-201008">inboard starters</a> and <a href="/7236-arco-starting-charging-starters-outboard-201009">outboard starters</a> utilize high-performance permanent magnet gear reduction technology, ensuring powerful cranking even in cold-start situations. Whether you're maintaining a fishing boat, pleasure craft, or commercial vessel, ARCO's extensive application catalog covers major engine manufacturers including Mercury, Yamaha, Volvo Penta, MerCruiser, and OMC.</p><p>Beyond their traditional marine engine components, ARCO has expanded into high-energy charging solutions through their Zeus product line, which includes high-output alternators in 12V, 24V, and 48V configurations, along with Bluetooth-enabled voltage regulators. This innovation addresses the growing electrical demands of modern boats equipped with electronics, navigation systems, and house battery banks. ARCO's commitment to manufacturing in America means faster availability, with over six months of inventory typically in stock, and direct technical support from the engineers who design and build their products.</p>

Part Number

BI-1203-3A
07/13/2036 12:06 PM
Sale Price

$159.93

1 left at this price

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Usually delivered within 2 days

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Product Details

The Arco Marine BI-1203-3A is a solid-state battery isolator designed for marine inboard and outboard applications. This unit handles 1 alternator and 3 batteries with a maximum current rating of 120 amps. It's rated for use with 10 to 350-amp alternators on 12, 24, or 32-volt negative ground systems and includes an exciter terminal for proper voltage regulation.

Key Features:

  • 120-amp maximum capacity with 1 alternator and 3 battery configuration
  • Solid-state design allows current flow in one direction only, preventing higher-charged batteries from discharging into lower-charged batteries
  • Automatic proportional charging—both batteries receive charge according to their individual needs whenever the engine is running
  • Compatible with battery selector switches without requiring position changes for dual-battery charging
  • Rated for 10 to 350-amp alternators on 12V, 24V, or 32V negative ground systems
  • Includes exciter terminal for voltage regulation

This battery isolator provides intelligent charge distribution, automatically directing alternator output to the batteries that need it most regardless of selector switch position. Ideal for marine vessels requiring reliable dual or triple battery management.

Important Compatibility Note: This battery isolator cannot be used on 12-volt charging systems with 24-volt trolling motors or newer outboard engines equipped with rectifier-regulator charging systems.

Great delivery service. Quickly delivered

Good experience

Great product, great price and shipped on time without any damage.

Amazed that I got the item ordered so quickly!

Order online went smoothly. Even better than calling CS directly.

So far so good , Lucas is great product and prices are very good

Product was as described

super quick and easy

Checkout was seamless and quick

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