A single stacking module from the OutBack line, designed around lead acid like the Radian. No CAN battery port, so the charge profile is the entire safety layer.
Published figures
- Continuous output
- 3,600 W
- Surge output
- 7,200 W
- Battery voltage window
- 40 to 64 V
- Max charge current
- 85 A
- Battery comms
- Modbus
- Output
- 120 V single phase
- Grid interactive
- Yes
- PV input
- External charge controller
What this inverter will and will not do
- It works alongside the utility, which means an interconnection agreement, a permit, and an inspection in most jurisdictions. Budget months, not weeks, for that process.
- Output is single phase 120 V. A well pump, an electric dryer, or anything else expecting 240 V needs an autotransformer or a different inverter.
- Battery communication runs over Modbus, and closed loop still depends on both sides agreeing on a message format rather than only on a bus standard.
- No solar charge controller is built in. A working system needs a separate MPPT, which is cost and cabinet space that is easy to leave out of a first budget.
Sizing a battery bank for it
This inverter delivers up to 85 amps of charge current, and that figure, not your daily energy use, sets the minimum pack count. Every battery below is shown at the smallest bank that can absorb the full charge rate.
| Battery | Packs needed | Bank capacity | Voltage window | Charge accepted | Comms | Result |
|---|---|---|---|---|---|---|
| Pylontech US5000 | 1 | 4.8 kWh | 44.5 to 54.0 V | 100 A | CAN, RS485 | Conflict |
| Dyness B4850 | 2 | 4.8 kWh | 44.0 to 54.0 V | 100 A | CAN, RS485 | Conflict |
| Freedom Won eTower 5 | 1 | 5.0 kWh | 44.0 to 57.6 V | 100 A | CAN | Conflict |
| EG4 LifePower4 48V 100Ah | 1 | 5.1 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| EG4 LL-S 48V 100Ah | 1 | 5.1 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| SOK 48V 100Ah Server Rack | 1 | 5.1 kWh | 46.4 to 56.0 V | 100 A | CAN, RS485 | Conflict |
| Pytes E-BOX 48100R | 1 | 5.1 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| Jakiper JK48V100 48V 100Ah | 1 | 5.1 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| Vatrer 48V 100Ah | 1 | 5.1 kWh | 40.0 to 58.4 V | 100 A | RS485 | Conflict |
| Ruixu 48V 100Ah Server Rack | 1 | 5.1 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| EG4 LifePower4 V2 48V 100Ah | 1 | 5.1 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| Pytes V5 48V 100Ah | 1 | 5.1 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| Pytes R-BOX 48V 100Ah | 1 | 5.1 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| Trophy Battery 48V 100Ah | 1 | 5.1 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| SunGold 48V 100Ah Rack | 1 | 5.1 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| Growatt ARK 2.5H | 2 | 5.1 kWh | 44.0 to 57.6 V | 100 A | CAN, RS485 | Conflict |
| Growatt ARK XH 5.1 | 1 | 5.1 kWh | 44.0 to 57.6 V | 100 A | CAN, RS485 | Conflict |
| Rich Solar 48V 100Ah | 1 | 5.1 kWh | 44.8 to 58.4 V | 100 A | RS485 | Conflict |
| Gobel Power GP-SR1-48100 | 1 | 5.1 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| Fortress eFlex 5.4kWh | 1 | 5.4 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| Discover AES 48-6650 | 1 | 6.7 kWh | 42.0 to 57.6 V | 130 A | CAN, Modbus | Unverified |
| Discover AES 42-48-6650 | 1 | 6.7 kWh | 42.0 to 57.6 V | 130 A | CAN, Modbus | Unverified |
| Pylontech US3000C | 2 | 7.1 kWh | 44.5 to 54.0 V | 148 A | CAN, RS485 | Conflict |
| SimpliPhi PHI 3.8 | 2 | 7.6 kWh | 44.0 to 57.6 V | 150 A | none | Unverified |
| BYD Battery-Box Premium LVS 8.0 | 1 | 8.0 kWh | 40.0 to 57.6 V | 250 A | CAN | Conflict |
| HomeGrid Stack’d 48V 9.6kWh | 1 | 9.6 kWh | 44.8 to 58.4 V | 150 A | CAN, RS485 | Conflict |
| Dyness PowerBox 48V | 1 | 9.6 kWh | 44.0 to 54.0 V | 100 A | CAN, RS485 | Conflict |
| LiTime 48V 100Ah | 2 | 10.2 kWh | 40.0 to 58.4 V | 100 A | none | Unverified |
| SOK 48V 200Ah | 1 | 10.2 kWh | 46.4 to 56.0 V | 200 A | CAN, RS485 | Conflict |
| Jakiper JK48V200 48V 200Ah | 1 | 10.2 kWh | 44.8 to 58.4 V | 200 A | CAN, RS485 | Conflict |
| BigBattery Owl 48V | 2 | 10.2 kWh | 44.8 to 58.4 V | 100 A | none | Unverified |
| LiTime 48V 50Ah | 4 | 10.2 kWh | 40.0 to 58.4 V | 100 A | none | Unverified |
| LiTime 48V 200Ah | 1 | 10.2 kWh | 40.0 to 58.4 V | 100 A | none | Unverified |
| Vatrer 48V 200Ah | 1 | 10.2 kWh | 40.0 to 58.4 V | 200 A | RS485 | Conflict |
| Ruixu Lithi-2 48V 200Ah | 1 | 10.2 kWh | 44.8 to 58.4 V | 200 A | CAN, RS485 | Conflict |
| CHINS 48V 100Ah | 2 | 10.2 kWh | 40.0 to 58.4 V | 100 A | none | Unverified |
| Redodo 48V 100Ah | 2 | 10.2 kWh | 40.0 to 58.4 V | 100 A | none | Unverified |
| Power Queen 48V 100Ah | 2 | 10.2 kWh | 40.0 to 58.4 V | 100 A | none | Unverified |
| ECO-WORTHY 48V 100Ah | 2 | 10.2 kWh | 40.0 to 58.4 V | 100 A | none | Unverified |
| Basen 48V 200Ah | 1 | 10.2 kWh | 44.8 to 58.4 V | 200 A | CAN, RS485 | Conflict |
| Victron Lithium Smart 48V 200Ah | 1 | 10.2 kWh | 40.0 to 57.6 V | 200 A | CAN | Conflict |
| EG4 PowerPro WallMount 48V 280Ah | 1 | 14.3 kWh | 44.8 to 58.4 V | 200 A | CAN, RS485 | Conflict |
| EG4 WallMount Indoor 48V 280Ah | 1 | 14.3 kWh | 44.8 to 58.4 V | 150 A | CAN, RS485 | Conflict |
| BigBattery Rhino 2 48V | 1 | 14.3 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| Seplos Mason 280 48V | 1 | 14.3 kWh | 44.8 to 58.4 V | 200 A | CAN, RS485 | Conflict |
| BigBattery Etheron 48V 15kWh | 1 | 15.4 kWh | 44.8 to 58.4 V | 150 A | CAN, RS485 | Conflict |
| Fortress eVault Max 18.5kWh | 1 | 18.5 kWh | 44.8 to 58.4 V | 133 A | CAN, RS485 | Conflict |
| Fortress eVault 18.5kWh | 1 | 18.5 kWh | 44.8 to 58.4 V | 100 A | CAN, RS485 | Conflict |
| HomeGrid Stack’d 48V 19.2kWh | 1 | 19.2 kWh | 44.8 to 58.4 V | 300 A | CAN, RS485 | Conflict |
| Rolls S-480 48V AGM | 1 | 20.6 kWh | 42.0 to 58.0 V | 85 A | none | Unverified |
Fuse and cable for the battery run
Running flat out this inverter pulls about 75 amps at 48 volts, and a surge takes it to roughly 150 amps. Size the protection for the peak, not the average: a 100 amp Class T fuse at the battery positive terminal and 2 AWG cable on the battery run. Class T rather than a standard fuse because a 48 volt lithium bank can deliver enough short circuit current to arc across a fuse that lacks the interrupt rating. Confirm the sizing against your installation manual, which accounts for run length and ambient temperature.
Communication
No manufacturer document tracked here names a specific battery for closed-loop operation with this inverter.
Where the figures come from
Manufacturer documents: OutBack Power documentation. Figures here should be read against the revision that covers your serial number, because manufacturers revise specifications without changing the model name.
Where to buy the OutBack VFXR3648A
Current listings and prices for the OutBack VFXR3648A and the parts most builds need alongside it.
Check price on AmazonBattery cable and lugsClass T fuse and holderAffiliate links. As an Amazon Associate this site earns from qualifying purchases, at no extra cost to you. Prices and stock change often, and a listing appearing here is not a statement that the pairing above is approved.
Questions people actually ask
How many batteries does the OutBack VFXR3648A need?
Enough packs to accept 85 amps of charge current. With a 100 amp rack battery that is 1 of them. Fewer will run the system perfectly well with the charge rate capped in settings, and capping it costs you charging speed on short winter days.
What size fuse and cable does the OutBack VFXR3648A need?
It draws about 75 amps continuously at 48 volts and roughly 150 amps during a surge. That points at a 100 amp Class T fuse and 2 AWG cable for the battery run, sized for the fuse rather than the average load. Confirm against the figure in your installation manual, which accounts for run length and ambient temperature.
Which batteries have a documented pairing with the OutBack VFXR3648A?
None of the batteries tracked here have a manufacturer document naming this inverter for closed-loop operation. That is a documentation gap, not a verdict on the hardware.
Can the OutBack VFXR3648A run a well pump?
It surges to 7,200 watts, about 150 amps from the battery. Whether the pump starts depends on the pack as much as the inverter, because the BMS is what interrupts a surge it is not rated for. The pairing pages check that figure per battery. A bank of 1 EG4 LifePower4 48V 100Ah is the smallest configuration on this site with a published surge rating that covers it.