The Victron MultiPlus-II 48/4500/55-32 combines a sine wave inverter, a multi-stage battery charger and an automatic transfer switch in one enclosure. Built for 48V battery systems on a 230V AC supply, it suits off-grid installs, backup power and solar storage where a single unit needs to handle both charging and inversion. This is a battery charger inverter designed to accept a generator or grid feed and switch to battery power the moment that source drops out.

Key features

• Inverter output, 4500VA continuous at 230V AC from a 48V DC bank.
• Battery charger, 55A built in, with an adaptive algorithm to suit different battery chemistries.
• AC input, 32A rating, for connection to a generator or the grid.
• PowerAssist, supplements AC input from the battery when load demand exceeds the available supply.
• Transfer switch, switches source with a typical changeover of under 20 milliseconds.
• Dual AC outputs, AC-Out-1 stays live on inverter power; AC-Out-2 drops non-critical loads when running on battery.

System integration

VE.Bus lets several units run in parallel, or in split-phase and three-phase arrangements. Paired with a Victron GX device such as a Cerbo GX, the MultiPlus-II can be set up for ESS operation in grid-tied or hybrid solar storage systems. Configuration and firmware updates go through VEConfigure software via a VE.Bus to USB interface.

Applications

• Off-grid homes and commercial sites running a 48V battery bank.
• Backup power where fast automatic transfer from grid or generator to battery matters.
• Solar storage systems using Victron ESS with a GX monitoring device.
• Generator-assisted off-grid setups, where PowerAssist allows a smaller generator to be used.
• Marine and vehicle power systems built around a 48V bank.