UPS battery backupsENERGY STAR certified
Amazon Basics ABST400
400 VA / 255 W line interactive UPS.
Capacity
400 VA
255 W real power
Topology
Line Interactive
Efficiency
98.3%
weighted, as tested
Runtime @ 50%
7 min
2 min at full load
A UPS has two ratings and the lower one is the limit. This unit is rated 400 VA and 255 W, so the equipment plugged into its battery outlets should draw no more than about 204 W if you want the usual 20% headroom. How to size a UPS.
Its weighted efficiency of 98.3% compares with a median of 98.1% across 38 certified units within 25% of its capacity. With nothing plugged in it still draws 2.6 W, about $2.98 a year at 13¢/kWh just to stand ready.
- Maker
- Amazon Basics
- Model
- ABST400
- Apparent power rating
- 400 VA
- Real power rating
- 255 W
- Power factor
- 0.64
- Topology
- Line Interactive
- Intended use
- Consumer, Commercial
- Battery
- Valve Regulated Lead-acid Battery
- Runtime at 50% load
- 7 min
- Runtime at 100% load
- 2 min
- Battery warranty
- 1 yr
- Weighted efficiency
- 98.3%
- Efficiency at 25 / 50 / 75 / 100% load
- 96.4% / 98.3% / 98.8% / 99.1%
- Input power at no load
- 2.6 W
- Rack mountable
- No
- Rated input voltage
- 120 V
- Rated output voltage
- 120 V
- Connections
- None
- Size (H x W x D)
- 82 x 110 x 184 mm
- Maker take-back program
- Yes
- On the market since
- Nov 2017
- ENERGY STAR certified
- 16 Sep 2019
Source: ENERGY STAR certified uninterruptible power supplies dataset, US EPA, record 2333805, data build 2026-09-29. Figures are as the maker certified them. How we use this data.
Other makers
Machines comparable to the ABST400
Certified UPS units from other makers within 25% of its VA rating.
| Model | Capacity | Topology | Efficiency | Runtime @ 50% |
|---|---|---|---|---|
| APC Back-UPS 400VA 120V Slim Flexible Mounting | 400 VA / 220 W | Passive Standby | 98.5% | 20 min |
| Vertiv PUL-400LVT | 400 VA / 240 W | Passive Standby | 97.8% | 25 min |
| CyberPower ST425 | 425 VA / 260 W | Passive Standby | 97.8% | 6 min |
| CyberPower CP425G3 | 425 VA / 255 W | Passive Standby | 97.9% | 8 min |
| CyberPower SE450G1 | 450 VA / 260 W | Passive Standby | 97.8% | 6 min |
| CyberPower CP350COM | 350 VA / 255 W | Passive Standby | 97.9% | 8 min |
Amazon Basics
More Amazon Basics UPS battery backups
| Model | Capacity | Topology | Efficiency | Runtime @ 50% |
|---|---|---|---|---|
| ABMT1000 | 1,000 VA / 600 W | Line Interactive | 98.6% | 9 min |
| ABMT1500 | 1,500 VA / 900 W | Line Interactive | 98.6% | 12 min |
| ABMT1500a | 1,500 VA / 900 W | Line Interactive | 98.8% | 11 min |
| ABST600 | 600 VA / 360 W | Line Interactive | 98.9% | 9 min |
| ABST800 | 800 VA / 450 W | Passive Standby | 98.5% | 12 min |
| ABST800 | 800 VA / 450 W | Line Interactive | 98.8% | 14 min |
| S175UC | 850 VA / 510 W | Line Interactive | 98.7% | 9 min |