Victron Energy MultiPlus Inverter/Charger, 12V DC, 120V AC, True Sine Wave, VE.Bus, 16A Transfer Switch

Overview

The Victron Energy MultiPlus is a 12V, 120V AC inverter/charger range for boats that need inverter power, battery charging, and shore or generator transfer in one unit. The range covers 500VA, 800VA, and 1200VA models, with matching house-battery charge currents of 20A, 35A, and 50A. Each model outputs 120V AC at 60Hz from a 12V battery bank and uses a 16A AC transfer switch.

This unit is a good fit for marine electrical systems where a 12V house bank powers selected 120V AC loads when away from shore power, then recharges from shore power or a generator when AC input is available. PowerControl helps manage limited shore or generator input, while PowerAssist can add battery power during short peak loads.

The IP21 Steel/ABS enclosure belongs in a dry, ventilated electrical space such as a cabin locker, electrical compartment, or protected utility area. It should not be treated as a deck-mounted or washdown-rated device.

Key features

• Combines a true sine wave inverter, adaptive battery charger, and 16A AC transfer switch in one onboard power unit.
• Built for 12V battery systems, with a 9.5 to 17V DC input range and 120V AC, 60Hz output.
• PowerControl lets the system respect a set shore or generator current limit while using available capacity for charging.
• PowerAssist can supplement limited shore or generator power from the battery during short peak-load moments.
• VE.Bus RJ45 communication port supports remote monitoring and system integration with compatible Victron equipment.
• Supports setup through DIP switches, VictronConnect, or VE.Configure with the proper interface.
• Includes support for a battery temperature sensor and a 1A starter-battery trickle charge output.
• IP21 enclosure is suited to protected mounting locations away from direct spray, washdowns, and exposed UV.

Variants

This MultiPlus range is offered in three configurations for different 12V house-bank and 120V AC load requirements.

The variant options change the inverter rating and house-battery charger current. The 120V AC output, 16A transfer switch, VE.Bus port, PowerControl, PowerAssist, and 12V battery platform remain consistent across this group.

• PMP121500100: 500VA inverter rating with 20A charger current. This is the smallest model in the group, with lower charging current for lighter onboard AC demand.
• PMP121800100: 800VA inverter rating with 35A charger current. This model sits between the 500VA and 1200VA versions for systems that need more inverter capacity and faster house-bank charging than the entry model.
• PMP122120100: 1200VA inverter rating with 50A charger current. This configuration carries the highest inverter rating and house-battery charging current in this three-model range.

Electrical and system integration

The MultiPlus works as the link between the DC battery system and the boat's 120V AC loads. When shore power or generator power is present, the transfer switch passes AC through and the charger can recharge the house battery. When AC input is not available, the inverter supplies 120V AC from the 12V battery bank for appropriate onboard loads.

The VE.Bus port gives the unit a place in a larger Victron system. With compatible GX equipment, system information can be viewed centrally and monitored remotely. For setup work, VictronConnect or VE.Configure can be used with the required interface.

Installation and mounting

Plan the installation around the selected model's size, cable routing, ventilation, and access to the connection area. The 500VA model measures 311 x 182 x 100 mm and weighs 4.4 kg, the 800VA model measures 360 x 240 x 100 mm and weighs 6.4 kg, and the 1200VA model measures 406 x 250 x 100 mm and weighs 8.2 kg.

Battery connection size also changes by model: 16mm2 for 500VA, 25mm2 for 800VA, and 35mm2 for 1200VA. The AC connection uses a G-ST18i connector. Match the DC cabling, AC wiring, grounding, ventilation, and overcurrent protection to the chosen model and the vessel's electrical standard.

Battery charging and use on board

The charger supports common house-battery types used on boats, including lithium, sealed, AGM, gel, and flooded batteries. The four-stage adaptive charging behavior helps the charger respond to battery condition instead of simply applying a fixed routine.

This range makes sense on coastal cruising boats, fishing boats, and compact liveaboard systems that run selected 120V AC loads while keeping a 12V house bank charged from shore power or a generator. It also suits installations where limited shore input needs to be managed carefully so charging does not overload the available AC supply.