Victron Argodiode 140-3AC Battery Isolator 3 Batteries 140A

The Victron Argodiode 140-3AC is a diode-based battery isolator designed for 12V, 24V and 48V systems where a single alternator must charge up to three independent battery banks simultaneously. It is suited to marine, vehicle and off-grid applications where preventing discharge between banks is a hard requirement.

Key Features

• 140A continuous rated current, suitable for high-demand charging systems with large alternators.
• Supports up to three separate battery banks from a single alternator input, with full electrical isolation between banks.
• Diode isolation prevents any battery bank from discharging into another, regardless of state of charge differences.
• Compatible with 12V, 24V and 48V DC systems, making it usable across a wide range of vehicle and off-grid configurations.
• Aluminium heat sink body for passive thermal management under sustained high-current operation.
• Compact, robust construction with straightforward busbar-style connections for clean installation.

Product Overview

The Argodiode 140-3AC uses Schottky diodes to split alternator output between multiple battery banks without any electronic switching or control wiring. Current flows from the alternator input through to each battery output independently. If one bank is fully charged and another is depleted, the diodes ensure charge flows where it is needed without any back-feed between banks.

The trade-off with diode isolators is a voltage drop across each diode, typically 0.5V to 0.7V under load. This means the alternator output voltage seen at the batteries is slightly lower than the alternator terminal voltage. In systems with a smart alternator or external voltage regulator, this can be compensated by raising the regulator set point. Victron's own battery chargers and MPPT controllers can also be configured to account for this offset. Installers should factor this into system design, particularly for AGM or lithium battery banks with tighter charge voltage tolerances.

The 140A rating covers the total input current. Distribution across the three output banks is determined by the relative state of charge and internal resistance of each battery. The unit weighs 1kg and is supplied in retail packaging, making it suitable for both trade and end-user supply.

Specifications

• SKU: ARG140301020R
• GTIN: 8719076019107
• Maximum input current: 140A
• Number of battery outputs: 3
• Alternator inputs: 1 (AC = single alternator input)
• Compatible system voltages: 12V, 24V, 48V
• Weight: 1kg
• Packaging: Retail

Applications

• Marine vessels with separate starter, domestic and bow-thruster battery banks charged from a single alternator.
• Motorhomes and campervans requiring isolation between the vehicle starter battery and one or more leisure banks.
• Off-grid cabins or vehicles with alternator charging and multiple battery banks serving different loads.
• Commercial vehicles where auxiliary battery banks must remain isolated from the engine start battery.
• Retrofit installations replacing older split-charge relay systems where diode isolation is preferred.

What Is Included

• 1 x Victron Argodiode 140-3AC diode battery isolator (retail packaging)

Installation Notes

Installation should be carried out by a qualified auto-electrician or marine electrician familiar with high-current DC systems. The unit must be mounted on a surface that allows adequate airflow around the heat sink, as thermal performance depends on passive convection. Ensure all cable connections are correctly rated for 140A continuous use and that appropriate fusing is fitted on the alternator feed. Account for the diode voltage drop when setting alternator or regulator output voltage, particularly with AGM or lithium battery chemistries. For marine installations, follow NMEA or RYA wiring guidelines as applicable.