Ignitions and Electrical› Charging Systems

ARCO MARINE

BATTERY ISOLATOR 1 ALTERNATOR 3 BATTERIES 120 AMP MAX INBOARD AND OUTBOARDIN

$258.10

SKU: A09I BI-1203-3A

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In Stock
Ships by Jun 14
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Non-Returnable Item

Description

The Arco Marine BI-1203-3A is a battery isolator designed for marine applications. It can handle one alternator, three batteries, and a maximum of 120 amps. This solid-state device allows electrical current to flow in one direction only, preventing a higher-charged battery from discharging into a lower-charged one.

Both batteries are automatically charged in proportion to their needs whenever the engine is running. The isolator also provides proportioning of the alternator's output current to the batteries as required. It is rated for use with 10 to 350-amp alternators on 12, 24, or 32-volt negative ground systems and includes an exciter terminal.

Fitment

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Specifications

BrandARCO MARINE
Part NumberA09I BI-1203-3A

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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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