Checked as a bank of 3 packs, which is the smallest number that accepts this inverter’s 250 amp charge current. Fewer packs still run the system, with the charge rate capped in inverter settings.
Full specifications: EG4 12000XP and Rolls S-480 48V AGM.
The four checks
Voltage window: Overlapping window 42 to 58 V
The inverter operates from 40 to 60 volts and the battery cuts off outside 42 to 58 volts. Both stay inside 42 to 58 volts, which covers a normal LiFePO4 charge and discharge cycle with margin at both ends.
Charge current: 250 A into a 255 A limit
The inverter tops out at 250 amps and the battery accepts 255 amps, so a default install cannot overrun the pack. Adding batteries in parallel raises the accepted current further.
Surge rating: Battery surge figure unpublished
A surge to 24000 watts draws roughly 500 amps at 48 volts. This battery publishes a 600 amp continuous rating and no separate surge figure, and continuous is the wrong number to check a motor start against. Confirm the peak rating and its duration with the manufacturer before running motor loads.
Closed-loop communication: Battery publishes no protocol
The inverter speaks CAN, RS485. This battery publishes no communication protocol, so closed loop is not on the table and the pairing runs on voltage limits set by hand. Confirm with the manufacturer that no port exists before assuming it.
What this means when you install it
Set the inverter charge current to 250 amps or less. That is the inverter maximum, which this bank can absorb. Protect the battery run with a 350 amp Class T fuse and two parallel runs of 2/0 cable wired to a busbar rather than daisy chained, so all 3 packs share current evenly.
The inverter speaks CAN, RS485. This battery publishes no communication protocol, so closed loop is not on the table and the pairing runs on voltage limits set by hand. Confirm with the manufacturer that no port exists before assuming it.
Figures side by side
| Field | EG4 12000XP | Rolls S-480 48V AGM |
|---|---|---|
| Voltage window | 40 to 60 V | 42.0 to 58.0 V |
| Charge current | 250 A delivered | 255 A accepted (3 packs) |
| Peak draw | 24,000 W surge | surge unpublished |
| Usable capacity | n/a | 61.8 kWh (3 packs) |
| Comms | CAN, RS485 | none |
Manufacturer documents
Manufacturer documents: EG4 product and document library. Figures here should be read against the revision that covers your serial number, because manufacturers revise specifications without changing the model name.
Manufacturer documents: Rolls Battery documentation. Figures here should be read against the revision that covers your serial number, because manufacturers revise specifications without changing the model name.
Both units, current pricing
Prices on these move week to week, and the battery is usually the line item worth watching.
EG4 12000XP on AmazonRolls S-480 48V AGM on AmazonComms cableAffiliate 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.
Other pairings for the Rolls S-480 48V AGM
EG4 6000XP with Rolls S-480 48V AGM
Partial match, some fields unverified.
EG4 18KPV with Rolls S-480 48V AGM
Partial match, some fields unverified.
EG4 FlexBoss21 with Rolls S-480 48V AGM
Partial match, some fields unverified.
Sol-Ark 12K with Rolls S-480 48V AGM
Partial match, some fields unverified.
Questions people actually ask
Will the EG4 12000XP work with the Rolls S-480 48V AGM?
Partial match, some fields unverified. Checked as a bank of 3 packs, which is the smallest number that accepts this inverter’s 250 amp charge current. Fewer packs still run the system, with the charge rate capped in inverter settings. The four checks below show which field produced that result.
What does this pairing cost to wire up?
Beyond the two units, a 350 amp Class T fuse and holder, two parallel runs of 2/0 battery cable cut to matched lengths, and a busbar if you are running 3 packs. A comms cable if you intend to attempt closed loop, and the pinout is rarely the same between brands.
Where does this pairing go wrong in practice?
The inverter speaks CAN, RS485. This battery publishes no communication protocol, so closed loop is not on the table and the pairing runs on voltage limits set by hand. Confirm with the manufacturer that no port exists before assuming it.
What charge current should I set?
The inverter tops out at 250 amps and the battery accepts 255 amps, so a default install cannot overrun the pack. Adding batteries in parallel raises the accepted current further.