Victron Energy MultiPlus-II inverter/charger 3000VA 2x120V 12V 120A — Power Assist, pure sine output

The Victron Energy MultiPlus-II 2x120V 3000VA 12V 120A is a combined inverter and charger that delivers uninterrupted, high-quality AC power with Power Assist for limited shore or generator sources.

The MultiPlus-II blends a pure sine wave inverter, a multi-stage battery charger and intelligent power management into a single unit built for marine, mobile and off-grid installations. Rated 3000VA with a 12V/120A charger and dual 120V outputs, this model supports parallel and three-phase configurations for larger systems. Its rapid 20 ms transfer time ensures mains-like continuity when switching to battery power, while the Power Assist function prevents overloads by supplementing weak AC sources with battery power.

How does the MultiPlus-II keep devices running during a power interruption?

When AC mains or generator power drops or fails, the MultiPlus-II instantly converts DC battery power to AC with a transfer time of about 20 milliseconds. This near-instant changeover maintains operation of sensitive electronics and refrigerators without noticeable interruption.

• 20 ms transfer time for seamless backup
• Pure sine wave output for sensitive equipment
• Automatic priority between shore, generator and battery

What is Power Assist and when does it matter?

Power Assist prevents overloads of limited AC sources by adding inverter power from the battery when peak demand exceeds shore or generator capacity. This is especially useful when starting motors, air conditioners or multiple heavy loads at once.

• Boosts available AC power during short peaks
• Reduces generator sizing needs and shore power trips
• Configurable thresholds to match system behavior

Can the unit scale for larger systems or three-phase setups?

Yes — up to six MultiPlus-II units can run in parallel to increase continuous and surge power. For three-phase applications, three units can be configured to supply balanced three-phase output, making this model flexible for larger vessels, RVs and off-grid homes.

• Parallel up to six units for higher AC capacity
• Three-unit three-phase configuration available
• Networked control and AC distribution compatibility

How robust and installation-ready is this inverter/charger?

The MultiPlus-II is engineered for demanding environments with professional-grade components and protections. It supports remote monitoring and configuration, multiple AC and DC safety features, and is intended for marine, vehicle and land-based off-grid use where reliability matters.

• Built-in multi-stage charger and safety protections
• Remote monitoring and firmware update capable
• Designed for continuous professional use in harsh environments

Who is this for: The Victron Energy MultiPlus-II 2x120V 3000VA 12V 120A is aimed at boat owners, RV users, professional installers and off-grid homeowners who need a compact, scalable inverter/charger that handles sensitive electronics, supports temporary AC source limitations and can grow into parallel or three-phase systems. Choose this unit when seamless backup, power-peak support and flexible system expansion are priorities—without sacrificing professional-grade control and safety features.