OutBack Radian GS4048A
For a small off-grid home that needs 240 V for a well pump but only 4 kW of steady load. Hard to find now, so check stock before designing around it.
Solar Cellz USA $2,995.75$2,995.75
The OutBack Radian GS4048A is the better 48V inverter overall, rated 3.7 to 3.0. The OutBack Radian GS4048A leads on safety listing, warranty and efficiency. The Sigineer APC3048D wins on value. The Sigineer APC3048D costs $2,196.75 less ($799 vs $2,995.75).
Sigineer APC3048D
A heavy, surge-strong 3,000 W 48 V inverter-charger for off-grid or backup systems on a budget, where a UL listing is not required.
Sigineer $799$799
Prices were last checked October 24, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the OutBack Radian GS4048A for safety listing (ETL listed to UL 1741 (2nd Ed. with supplement SA) and CSA C22.2 No. 107.1 vs no UL 458 or UL 1741 listing stated), warranty (5-year warranty vs 1-year warranty) and efficiency (93% peak efficiency (maker rating) vs 88% peak efficiency (maker rating)).
- Choose the Sigineer APC3048D for value ($0.27 per continuous watt vs $0.75 per continuous watt).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every split-phase inverter-chargers 48V inverter; a clear win is highlighted. How we rank explains each one.
| Factor weight | OutBack Radian GS4048A | Sigineer APC3048D |
|---|---|---|
| Overall rating | 3.7/5 | 3.0/5 |
| Value 30% | 0 $0.75 per continuous watt | 63 $0.27 per continuous watt |
| Idle draw 15% | 95 34 W idle with nothing plugged in | 80 60 W idle with nothing plugged in |
| Safety listing 15% | 100 ETL listed to UL 1741 (2nd Ed. with supplement SA) and CSA C22.2 No. 107.1 | 0 no UL 458 or UL 1741 listing stated |
| Warranty 15% | 100 5-year warranty | 0 1-year warranty |
| Features 15% | 70 optional remote, app add-on, lithium charge profile, 120/240 V split-phase, hardwire terminal | 60 optional remote, lithium charge profile, 120/240 V split-phase, hardwire terminal; no app |
| Efficiency 10% | 89 93% peak efficiency (maker rating) | 33 88% peak efficiency (maker rating) |
Specifications
| OutBack Radian GS4048A | Sigineer APC3048D | |
|---|---|---|
| Output | ||
| Type | Pure sine wave inverter-charger | Pure sine wave inverter-charger |
| AC output | 120/240 V split-phase | 120/240 V split-phase |
| Continuous power | 4,000 W | 3,000 W |
| Surge power | 6,000 W for 5 s | 9,000 W for 20 s |
| DC input range | 40 to 64 V | 40 to 64 V |
| Idle draw | 34 W (0.7 A at 48 V) | 60 W (1.2 A at 48 V) |
| Power-saving draw | 10 W | 15 W |
| Peak efficiency | 93% | 88% |
| Connections | ||
| AC outlets | 0 | 0 |
| GFCI outlets | No | No |
| Hardwire terminal | Yes | Yes |
| USB ports | None | None |
| Transfer switch | Yes | Yes |
| Pass-through rating | 50 A | 30 A |
| Charger | 57.5 A | 30 A |
| Lithium charge profile | Yes | Yes |
| Parallel units | Yes | No |
| Control and build | ||
| Remote | Optional extra | Optional extra |
| App | Optional add-on | No |
| Display | No | No |
| Safety listing | ETL listed to UL 1741 (2nd Ed. with supplement SA) and CSA C22.2 No. 107.1 | No |
| Design | Low-frequency (transformer) | Low-frequency (transformer) |
| Cooling | fan | fan |
| Dimensions | 28 x 16 x 8.75 in (71.1 x 40.6 x 22.2 cm) | 20 x 8.5 x 7 in (508 x 222 x 180 mm) |
| Weight | 82 lb | 49 lb |
| Warranty | 5 years | 1 year |
| Released | 2013-11 | - |