OutBack Radian GS8048A

The Radian predates the lithium era and was designed around lead acid, which is the single most important thing to know before pairing one with LiFePO4. There is no CAN battery port. Every protection limit has to be set by hand in the charge profile, and the BMS has no way to ask the inverter to stop, so the settings are the safety layer.

Published figures

Continuous output

8,000 W

Surge output

12,000 W

Battery voltage window

40 to 64 V

Max charge current

130 A

Battery comms

Modbus

Output

120/240 V split 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 120/240 V split phase from one box, so standard household 240 V loads run directly.
• 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 130 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.

Fuse and cable for the battery run

Running flat out this inverter pulls about 167 amps at 48 volts, and a surge takes it to roughly 250 amps. Size the protection for the peak, not the average: a 250 amp Class T fuse at the battery positive terminal and 4/0 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.

Questions people actually ask

Worth reading before you install

• How many batteries this inverter actually needs
• Split phase or single phase, and what it costs to get wrong
• Off grid or hybrid, and what each one will not do
• Cable sizing for the battery run