OutBack FX and VFX inverters are modular "building block" sinewave inverter / charger that can be used for both residential and commercial off-grid and grid-tie applications with battery storage. Inverters are available in two versions; a sealed, fan-cooled FX version and a higher powered ventilated VFX version. Each inverter/charger module is a complete power conversion system - DC to AC inverter, battery charger and AC transfer switch. Additional inverter/chargers can be added at any time either in parallel (120VAC), series (120/240VAC), or even three-phase (120/208) configurations. This allows the system to be tailored to the specific needs of the application, both at the time of installation and into the future. With the addition of an X-240 autotransformer, multiple inverter systems can be set up to provide 120/240 VAC split-phase output with the ability to provide full power on either 120VAC leg of the system. Up to ten inverters can be connected together to provide up to 36 kW of continuous power capacity with the use of the HUB and the MATE controller.