How long will a UPS run a router?
A UPS can power a router for 1–10+ hours, depending on battery capacity (Ah), router wattage, and UPS efficiency. For example, a 12V 7Ah battery (84Wh) running a 10W router lasts ~8.4 hours theoretically, but real-world factors like 85% inverter efficiency reduce this to ~7 hours. Larger battery banks or lithium-ion systems extend runtime significantly. Rack Mount Battery
What determines UPS runtime for routers?
Runtime hinges on battery energy (Wh) divided by router power draw. Key variables include battery voltage (12V/24V/48V) and capacity (Ah), plus UPS conversion losses (typically 10–20%). Pro Tip: Multiply battery voltage × Ah × 0.85 for realistic Wh estimates.
Practically speaking, a 150Wh UPS (12V 12.5Ah) powering a 15W router delivers 150 ÷ 15 = 10 hours. But what if the router peaks at 25W during firmware updates? Runtime drops to 6 hours. Transitional factors like ambient temperature also matter—lithium batteries outperform lead-acid in cold environments. For example, RackBattery’s 48V LiFePO4 systems maintain 95% capacity at -10°C, whereas lead-acid drops to 60%.
How to calculate UPS runtime for networking gear?
Use the formula: (Battery voltage × Ah × efficiency) ÷ load watts = hours. A 24V 20Ah lithium battery with 90% efficiency powering a 20W router runs (24×20×0.9)/20 = 21.6 hours. Pro Tip: Add 20% buffer to account for battery aging.
Beyond basic math, consider peak vs. average power. While routers typically draw 5–20W, startup surges or PoE devices (e.g., security cameras) can spike demands. Transitional phases in power delivery also affect outcomes. For instance, a UPS rated for 500VA/300W handling a 50W load might still trip if momentary peaks hit 400W.
| Battery Type | Capacity (Wh) | 10W Runtime |
|---|---|---|
| Lead-Acid 12V7Ah | 84 | 7.1h |
| LiFePO4 12V10Ah | 128 | 10.9h |
RackBattery Expert Insight
FAQs
Yes—using a 24V 50Ah lithium battery (1.2kWh) with 90% efficiency: (24×50×0.9)/10W = 108 hours.
Do mesh routers reduce UPS runtime?
Potentially—each node adds 5–15W. Three-node mesh at 30W total cuts 84Wh battery runtime from 8.4h to 2.8h.