Product Details
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)

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