Outback Power VFXR3648A-01 3.6 kW FXR Series Grid/Hybrid Inverter/Charger

The OutBack Power VFXR3648A-01 is a 3,600VA hybrid solar inverter charger in the FXR A-Series line, engineered for 48VDC battery systems that demand full grid-interactive capability alongside dependable off-grid backup. Built into a vented NEMA Type 1 die-cast aluminum enclosure rated for operation from −40°F to 140°F (−40°C to 60°C) and 93% relative humidity, the VFXR3648A-01 is purpose-built for installations where environmental conditions rule out sealed enclosures.

Key specifications

• Continuous output power: 3,600VA at 77°F (25°C); 30AAC continuous output current
• Surge capacity: 6,000VA instantaneous (100ms); 5,400VA (5-second); 4,000VA (30-minute)
• AC output voltage / frequency: 120VAC selectable (100–130VAC); 60Hz selectable (50Hz); output voltage regulation ±2.5%
• Nominal DC input voltage: 48VDC (42–68VDC operating range)
• Battery charger output: 45ADC continuous; 60AAC / 45ADC maximum; 2,450VA charging power; flooded, gel, AGM, lithium-ion, and flow chemistry supported
• AC input: 85–140VAC; 54–66Hz; 60AAC maximum input current; grid-interactive range 106–132VAC / 59.3–60.5Hz
• Typical efficiency: 93%; CEC weighted efficiency 91%
• Total harmonic distortion: typical <2%; maximum <5%
• Idle power: ~34W (full); ~9W (search mode); ~3W (off)
• Operating temperature: rated −4°F to 122°F (−20°C to 50°C); operating −40°F to 140°F (−40°C to 60°C)
• Enclosure: Vented NEMA Type 1 die-cast aluminum; 93% relative humidity rated
• Certifications: UL1741, CSA C22.2 No. 107.1, UL1778, Annex FF; RoHS compliant
• Dimensions: 13 H × 8.25 W × 16.25 L in. (33 × 21 × 41 cm); 61 lbs. (28 kg)
• Warranty: Standard 5-year; extended 10-year available

Grid-interactive with seven operating modes

The VFXR3648A-01 operates across the full spectrum of grid and off-grid configurations through seven programmable modes. In grid-interactive mode it functions within the 106–132VAC / 59.3–60.5Hz range required for utility interconnection, with a built-in automatic transfer switch (ATS) that satisfies UL1741 islanding requirements without external transfer hardware. OutBack's GridZero mode is particularly valuable in markets where net metering compensation has been reduced or capped—it directs stored solar energy to serve loads first, drawing from the grid only when the battery bank is depleted, without exporting surplus power that earns little or no credit. Generator assist mode allows the inverter to supplement a smaller generator when loads exceed its standalone capacity, reducing runtime and fuel consumption.

Vented design for demanding environments

Where sealed inverters derate or fail under sustained heat, humidity, or salt air exposure, the vented VFXR chassis maintains rated output. The die-cast aluminum NEMA Type 1 enclosure handles operating temperatures down to −40°F (−40°C) and up to 140°F (60°C), making it equally suited to cold-climate off-grid cabins and coastal or industrial sites with persistent corrosive air. Relative humidity tolerance of 93% covers the most demanding marine-adjacent and high-humidity installations.

Application scenarios

• Grid-tied residential backup: Grid-interactive 48V system with battery storage for seamless backup during outages, with ATS built in.
• Off-grid homestead or commercial building: Full off-grid operation at 3,600VA continuous with generator assist for extended autonomy.
• Coastal or marine-adjacent installations: Vented enclosure and wide humidity/temperature ratings handle salt air and condensation that would compromise sealed units.
• Scalable multi-inverter systems: Up to nine VFXR units can be stacked for three-phase operation, or ten in parallel for single-phase or split-phase configurations—expanding from a single 3.6kW unit to multi-inverter arrays as load requirements grow.

Modular, stackable architecture

The FXR A-Series modular design means capacity upgrades don't require replacing existing hardware—each additional VFXR unit adds to the system. Up to nine units combine for three-phase operation and up to ten run in parallel for single-phase or split-phase builds, reaching up to 36kW in a grid-tied 24V or 48V configuration. Each unit integrates natively with OutBack's MATE3s system controller and HUB communications bus, and when paired with a MATE3s, the VFXR3648A-01 gains access to OPTICS RE for remote monitoring and control from any location.

System compatibility

The VFXR3648A-01 operates on a 48VDC battery bank across a 42–68VDC input range, supporting flooded, gel, AGM, lithium-ion, and flow battery chemistries with multi-stage advanced charging profiles. A remote temperature sensor is included for charge compensation. AC input voltage and frequency limits are adjustable via the MATE3s controller to accommodate a wide range of generator outputs and utility feeds. The unit integrates directly with OutBack's FlexPower enclosures, FM and FLEXmax MPPT charge controllers, HUB communications bus, and MATE3s display and controller for a fully coordinated system.

Why choose the OutBack Power VFXR3648A-01?

The OutBack Power VFXR3648A-01 is the right choice for 48V system builders who need a fully certified hybrid solar inverter charger that operates reliably in harsh environments, supports true grid-interactive and GridZero modes, and scales modularly with additional OutBack units. At 93% typical efficiency with a 6,000VA instantaneous surge rating and a built-in ATS, it eliminates external transfer hardware while delivering the output quality and durability that mission-critical and off-grid installations require—backed by OutBack's standard 5-year warranty with a 10-year extended option.