Specifications
Reference data for the Web3 Pi UPS — a true DC UPS (no AC inverter) for the Raspberry Pi 5 and other USB-C PD devices. For behavior details see Power & Failover; for the data link see Host Integration and the Protocol Reference.
Power Output
| Parameter | Value |
|---|---|
| Output port | USB-C OUT — power + data over a single cable |
| Native Raspberry Pi 5 profile | 5.1 V / 5 A continuous — full Pi 5 power budget |
| USB-C PD output profiles | 5.1 V / 5 A · 9 V / 3 A · 12 V / 2.25 A · 15 V / 1.8 A, auto-negotiated |
| Cable requirement | E-marked USB-C cable for 5 A operation |
OUT is output only
Never feed power into the OUT port.
Power Input
| Parameter | Value |
|---|---|
| USB-C PD input (IN) | 12–20 V, auto-negotiated, 26 W minimum |
| DC barrel jack | 12–20 V DC, 5.5/2.5 mm connector |
| Recommended source | 45 W or more — a supply rated at least 45 W is required to deliver the full 27 W (5.1 V / 5 A) output; extra headroom also charges the battery under full load |
| Source selection | Automatic — with both external inputs connected, the higher voltage supplies the load |
| Power sources | 3 (USB-C PD, DC jack, battery) with seamless switching; output is maintained while any single source is available |
| Power path | Active — battery is bypassed when full and external power is present (less battery wear); instant failover to battery |
Battery
| Parameter | Value |
|---|---|
| Battery type | Sony NP-F series, 2S Li-Ion, 7.2 V nominal |
| Replaceable | Yes — user-replaceable, hot-swappable under external power |
| Charging | Automatic when external power is present; gentle-full target ≈ 8.1 V, modest charge current by design |
| Protection | Pack's internal protection circuit required — use quality NP-F packs |
Compatible battery options — runtime depends on your Raspberry Pi's workload. Use batteries from reputable manufacturers with a built-in protection circuit (BMS); we recommend Newell packs:
| Battery | Capacity | Runtime |
|---|---|---|
| Newell NP-F570 | 2600 mAh (18.7 Wh) | Shortest |
| Newell NP-F770 | 5200 mAh (38.5 Wh) | Mid-range |
| Newell NP-F970 | 9600 mAh (71 Wh) | Longest |
See Battery for charging behavior and swap procedure.
Interfaces
| Interface | Details |
|---|---|
| USB serial | Over the OUT cable; the UPS enumerates on the Pi as a Web3_Pi_UPS serial device — telemetry, event logging, graceful low-battery shutdown, and remote restart commands via the companion service |
| Display | 64 × 32 px monochrome OLED status display |
| Buttons | 2 push-buttons — screen navigation and local settings menu |
| Buzzer | Audible alarms (power loss, low battery) and UI feedback; can be muted |
| LTE-M module (optional) | Internal M.2 slot for the cellular module — remote monitoring without host networking, see Connectivity |
Physical
| Parameter | Value |
|---|---|
| Cooling | Passive — fanless, silent |
| Form factor | Compact standalone enclosure; connects by cable only (no GPIO header, no HAT stacking) |
| Enclosure compatibility | Works with any Raspberry Pi 5 case |
| Rear panel | USB-C IN + DC barrel jack |
