The Victron Energy Argofet 100-3 Battery Isolator is a FET-based 12V/24V isolator designed to charge up to three batteries from one alternator or a single-output battery charger without connecting the batteries together. Rated for 100A maximum charge and alternator current, it helps prevent an accessory battery from discharging the starter battery.
Its FET technology provides virtually no voltage loss, with less than 0.02V drop at low current and about 0.1V at higher current. A current-limited alternator energize input supports alternators that require B+ voltage to begin charging, making it a reliable solution for multi-battery charging systems.