EMAIL: sales@boaterstop.com PHONE: 919-951-4313

Free Shipping On All Orders Over $150.00

ARCO Marine  |  SKU: BI-1203-3A-ARC

ARCO Marine BI-1203-3A Battery Isolator f/10-350A Alternators on 12, 24 or 32V Negative Ground Systems [BI-1203-3A]

$171.99 $256.55
Shipping calculated at checkout.

Delivery and Shipping

All orders placed before 3 PM EST ship the same day

We offer multiple shipping options to ensure you get the part you need at a discount.

Best Way -$11.97

Ground -$14.69

2nd Day Air -$25.89

Overnight -$59.99

In addition, we can ship on your account or via a preferred method upon request.

Found a better price? Need faster shipping?

Call or email! 919-951-4313 or sales@boaterstop.com

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.

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

Payment & Security

Payment methods

  • American Express
  • Apple Pay
  • Diners Club
  • Discover
  • Google Pay
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.

Product Categories