Time Lux - online utility on ToolBox.
Battery energy Wh = (capacity/1000)·voltage×0.8; single-lamp duration = Wh/power; lamps needed N = ⌈area×lux/(lumens×utilization)⌉; system duration = Wh/(N×power).
| Item | Formula / Note | Source / Standard |
|---|---|---|
| Emergency lighting | ≥90 min egress lighting | GB 51309-2018 §3 |
| Illuminance | ≥1 lx corridors, ≥5 lx stairs | GB 51309-2018 §3.2 |
| Battery discharge | t = C/(I·k), k≈1.2–1.5 | GB/T 19638.2 |
| Self-contained type | ≥90 min per luminaire | GB 51309-2018 §3.3 |
| Central supply | ≤5 s switch (0.25 s critical) | GB 51309-2018 §3.6 |
| Maintenance | Annual ≥30 min discharge test | GB 51309 O&M |
根据电池容量与灯具参数计算消防应急照明的持续时间与所需灯具数量,用于应急照明系统配置与供电校核。