1. Introduction
This manual provides guidance on designing and configuring off‑grid Microgrid systems using the MultiPlus, Quattro, MultiPlus‑II, and Quattro‑II inverter/charger ranges. In these systems, multiple independent inverter/charger units are interconnected via a common AC bus.
With the introduction of Microgrid functionality, Victron Energy enables several independent Victron Power Banks to operate together on a shared AC bus, forming a larger, scalable off‑grid power system with decentralized load sharing. In this context, a Victron Power Bank refers to an inverter/charger system based on the MultiPlus, Quattro, MultiPlus‑II, or Quattro‑II range, connected to a single battery system.
By coupling multiple Power Banks using Hybrid Droop control, modular and redundant off‑grid systems can be realized, particularly in applications where the required inverter capacity exceeds the limits of a single system – up to 400 kW inverter capacity, without any central controller.
1.1. Advantages
Scalable beyond single-cluster limits: Multiple Victron Power Banks can be AC-coupled to exceed the power limits of a single VE.Bus system, enabling significantly larger off-grid systems without creating one large centralized inverter system.
Higher system redundancy and availability: Each Power Bank operates as an independent unit. If one bank is taken offline for service or experiences a fault, the remaining Power Banks continue supplying the AC bus, increasing overall system resilience.
Modular and distributed system architecture: Power Banks can be physically distributed (e.g., containerised units) and connected via a common AC bus, simplifying large-scale installations and enabling flexible system expansion over time.
1.2. Compatibility
See the listing below for a list of MultiPlus, MultiPlus-II, Quattro and Quattro-II models which are supported by this application.
You need to use a specific "Microgrid firmware" with the s97 subversion number. These firmware files are available from Victron Professional in the Firmware section.
The Microgrid functionality is also available in combination with the External Transfer Switch functionality for selected MultiPlus and MultiPlus-II models. Therefore, you need to use the "Microgrid – External Transfer Switch firmware" with the s98 subversion number. For configuration instructions regarding the External Transfer Switch setup, please also refer to the dedicated "MultiPlus-II External Transfer Switch application" manual.
Model | Firmware number |
|---|---|
MultiPlus 2000VA, MultiPlus 5000VA and larger | xxxxyyy-s97 |
MultiPlus 15000VA, MultiPlus 20kW | xxxxyyy-s97, xxxxyyy-s98 (if applicable) |
All MultiPlus-II | xxxxyyy-s97, xxxxyyy-s98 (if applicable) |
Quattro 3000VA and larger | xxxxyyy-s97 |
All Quattro-II | xxxxyyy-s97 |
Note: Supported models include 230 V, 120 V and 277 V variants. 2x120 V models are not supported.
1.3. Hardware requirements per Power Bank
Victron VE.Bus Inverter/Charger: One or multiple devices for 3-phase and/or phase-parallel operation are supported.
Circuit breakers and RCD: For circuit protection.
Electrical wiring: Refer to the Installation chapter for detailed instructions.
DC charging source: Each Microgrid Power Bank is required to have its own independent DC charging source.
Victron GX device: This is not mandatory, but strongly recommended.