The Victron Argodiode 120-2AC is a diode-based battery isolator that charges two separate battery banks at once from a single alternator or charger, without letting current pass between them. It suits marine, vehicle and off-grid systems where keeping battery banks apart matters.

Key features of this victron argodiode battery isolator

• Current rating, 120A continuous, supporting charging from a single alternator source.
• Two outputs, simultaneous, isolated charging of two independent battery banks.
• Diode isolation, prevents one battery bank discharging into another, protecting starter and service batteries from cross-drain.
• 2AC configuration, two Schottky diode pairs with a common anode input, reducing voltage drop compared with standard silicon diodes.
• Aluminium heatsink body, dissipates heat without needing active cooling.
• System voltage, compatible with 12V and 24V setups.

How it works

Schottky diodes give a lower forward voltage drop than conventional silicon diodes, typically 0.3V to 0.5V less. That means each battery bank receives voltage closer to what the alternator or charger actually outputs, which matters when charging lead-acid or AGM batteries that need accurate voltage regulation.

A single input from the alternator or DC charger splits across two separate diode paths to the two banks. Because the diodes only pass current one way, neither battery can discharge into the other, and a fault or deep discharge on one bank leaves the other unaffected. The aluminium body acts as the heatsink, so it should be mounted to a flat metal surface or bulkhead for adequate cooling at sustained high currents.

Applications

Fits marine vessels separating starter and domestic banks from one alternator, motorhomes and campervans with separate engine and leisure batteries, commercial vehicles running auxiliary loads such as refrigeration or tail lifts, off-grid setups with one charger feeding two banks, and 4x4 or overland vehicles with dual battery arrangements.

Installation notes

Mount on a thermally conductive metal surface for heat dissipation at full rated current. Cable connections must be rated for 120A, with appropriate fusing on the input and each output circuit. Account for the diode voltage drop when setting alternator or charger output voltage, and have installation carried out by a qualified electrician familiar with marine or vehicle wiring standards.

What's in the box

• 1 x Victron Argodiode 120-2AC battery isolator unit