Victron MultiPlus-II 12/24/48 V 3000

Hybrid Inverter Victron MultiPlus-II 12V 3000VA : The Premium 12V Solution for Mobile Applications

The Victron MultiPlus-II 12V 3000VA/120-32 represents European excellence in 12V hybrid inverters. Manufactured in the Netherlands by Victron Energy, this multifunctional inverter/charger integrates three essential functions in a compact casing: a 3000 VA pure sine wave inverter, a 120 A intelligent charger and an ESS (Energy Storage System) for optimum management of on-board energy.

Why choose a 12V system?

The 12V system is the standard, universal architecture for mobile and marine applications. This voltage offers numerous advantages for motorhomes, boats and nomadic installations:

• Universal compatibility: Almost all motorhome and marine equipment operates on 12V (lighting, pumps, refrigerators, ventilation).
• Low-voltage safety: fewer electrical risks, safer handling in damp environments (boats)
• Battery availability : Wide choice of compact, high-performance 12V lithium batteries (PowerBrick+, Victron LiFePO4)
• Existing infrastructure : Use of existing 12V wiring in the vehicle/boat
• Charging via alternator: Direct charging from the vehicle's alternator during journeys

With a switchover time of less than 20 milliseconds, your sensitive IT and electronic equipment will never be interrupted if the shore power is disconnected or the generator stops.

Performance and Technical Characteristics

PowerControl and PowerAssist: Essential Features for Mobile Applications

PowerControl is particularly useful in motorhomes and marinas where the power available is often limited. You set a maximum current (e.g. 10A on a 16A camping socket), and the MultiPlus-II automatically adjusts battery charging according to your instantaneous consumption, preventing the circuit-breaker from tripping.

PowerAssist turns your installation into a hybrid power station: when you start up a power-hungry appliance (air conditioning, microwave, electric kettle) that temporarily exceeds the power available on the platform, the MultiPlus-II instantly compensates by drawing on the batteries. Result: you get an extra 3000 VA while staying within your shore power limit.

ESS system: Optimised self-consumption

The MultiPlus-II 12V natively integrates ESS (Energy Storage System) functions, enabling intelligent energy management for fixed or semi-nomadic installations (tiny houses, mobile workshops):

• Optimised self-consumption mode: uses solar energy as a priority, stores the surplus in the batteries and only calls on the grid when necessary.
• Backup/UPS mode: Switches automatically to the batteries in less than 20 ms in the event of a mains power cut or disconnection from the shore power
• Peak Shaving Mode: Reduces consumption peaks to stay within the limits of a camping outlet or low-power generator

Integrated anti-islanding function ensures compliance with European safety standards.

Two independent AC outputs

The architecture with two AC outputs offers intelligent load management, particularly suitable for motorhomes and boats:

• Output 1 (priority - UPS): Uninterruptible power supply for critical equipment - computers, refrigerators, surveillance systems, alarms, essential lighting, etc.
• Output 2 (32A non-priority): Active loads only when the shore or generator is available - water heater, air conditioning, electric heating, washing machine, etc.

This separation optimises autonomy by discharging the batteries only for essential loads.

12V battery compatibility and sizing

The MultiPlus-II 12V accepts all types of 12V batteries with pre-programmed charging profiles:

• Lithium LiFePO4 12V: Best choice (95% efficiency, 3000-6000 cycles, low weight). Bluetooth communication with PowerBrick+ Smart and Victron LiFePO4 Smart 12V batteries.
• 12V AGM batteries: Excellent value for money (85% efficiency, 500-800 cycles), ideal for occasional use.
• 12V Gel batteries: Suitable for extreme temperatures and slow discharges (85% efficiency, 800-1200 cycles).

Typical configuration recommended for motorhomes: 2 PowerBrick+ 12V 150Ah batteries (300 Ah total) for 2-3 days of comfortable autonomy with 400-800Wp solar panels.

Typical applications of the MultiPlus-II 12V 3000VA

The MultiPlus-II 12V 3000VA is ideal for mobile and marine applications:

• Top-of-the-range motorhome / van: 400-800Wp solar panels, 300-400 Ah lithium batteries, 3-5 days autonomy without dock or generator.
• Pleasure boat / Sailboat: Solar generation + wind turbine + alternator, 400-600 Ah battery bank, shore power with current limitation
• Tiny house / Mobile home: Semi-nomadic installation, 1-2 kWp solar, 400-800 Ah batteries, occasional grid connection
• Professional vehicle: Mobile workshop, food-truck, converted lorry, emergency backup for sensitive equipment

Integration with Victron MPPT controllers

For a complete 12V photovoltaic installation, combine the MultiPlus-II with Victron SmartSolar MPPT controllers:

• SmartSolar MPPT 100/30: Up to 440W of panels, max voltage 100V, ideal for 1 panel 400W
• SmartSolar MPPT 100/50: Up to 700W of panels, max voltage 100V, for 2 400W panels
• SmartSolar MPPT 150/35: Up to 500W of panels, max voltage 150V, for 1 high-voltage panel
• SmartSolar MPPT 150/70: Up to 1000W of panels, max voltage 150V, for 2-3 panel installations

Consult our MPPT 2025 technical sizing guide to calculate the optimum configuration.

Advanced configuration and monitoring

Configuration is carried out using the free VEConfigure software and an MK3-USB interface (sold separately). For complete monitoring and remote supervision, the MultiPlus-II connects to Victron GX controllers (Cerbo GX, Ekrano GX) giving access to the free VRM Cloud portal:

• Real-time visualisation of production, consumption and battery status
• Detailed history of your trips and consumption
• Email alerts in the event of anomalies (deep discharge, overcharging)
• Remote modification of settings
• Geolocation of your vehicle via Cerbo GX GPS

To find out more about the Victron ecosystem, see our complete guide to MultiPlus-2, SmartSolar and Cerbo GX.

Scalability: Parallel and three-phase configurations

The MultiPlus-II 12V 3000VA can operate in parallel or three-phase configurations to suit your future needs:

Installation and Specific 12V Considerations

Installation of the MultiPlus-II 12V requires special attention to wiring due to high currents:

• DC wiring: Minimum cross-section 50 mm² for 12V battery (< 1.5m), DC fuse 200-250A depending on distance, connections tightened to recommended torque.
• Line losses: At 12V, losses are high - short, oversized cables are preferable.
• AC wiring: Minimum 2.5 mm² cross-section for 16A, 30 mA type A earth leakage circuit breaker
• Ventilation: 10 cm clearance around the inverter, sufficient natural ventilation
• Mounting: Vertical or horizontal wall mounting depending on space available, sturdy bracket (19 kg)

To size your cables correctly, use our free voltage drop calculator.

Wattuneed resources and tools

To optimise your mobile installation, use our free resources:

• Battery storage profitability calculator
• Advanced solar simulator to estimate your mobile production
• Photovoltaic sizing guide
• Technical support platform

Maintenance and warranty

The MultiPlus-II is designed to operate for 15-20 years with minimal maintenance:

• Every 6 months: Cleaning of ventilation grids, visual check of connections, tightening of DC terminals
• Every year: Mains/battery switchover test, general inspection
• Every 2 years: Firmware update if new features available

Victron Energy offers a 5-year manufacturer's warranty covering manufacturing defects and defective components. As an official distributor, Wattuneed provides full technical support before and after purchase.