Emergency UFO High Bay Lighting for Factory Areas During Outages — South Africa
The Challenge
- A South African factory runs 200W UFO high bays across its production floor. Grid outages — both scheduled and unscheduled — are a regular occurrence, so a dark floor is a real safety and downtime risk.
- They needed the high bays themselves to provide emergency lighting on outage at about 20% of normal output: safe illumination for evacuation and for low-light continuation of non-critical work, rather than having the whole floor go dark.
- The fittings had to keep an emergency light for a 2-hour period, with no separate backup luminaires and no manual intervention when power returned.
The Solution
- We fitted a self-contained emergency LED driver with a LiFePO4 (lithium iron phosphate) battery pack into each 200W UFO high bay. On mains loss the driver switches the luminaire to its battery and holds output at the specified ~20% — about 40W — for the full 2-hour period.
- The pack is sized to the emergency load: roughly 40W × 2 h ≈ 80 Wh usable, with margin, and LiFePO4 was chosen over NiCd because these outages are frequent: the battery is deeply cycled again and again, and LiFePO4 holds its capacity through that without the memory effect or scheduled replacement NiCd brings.
- Auto-recharge and restore on mains return means the emergency function needs no on-site attention through repeated outages.
- Built to IEC 60598-2-22 / EN 1838 emergency-lighting criteria; South Africa adopts the IEC / SANS family of luminaire standards.
Emergency Configuration
| Item | Specification |
|---|---|
| Luminaire | 200W UFO high bay |
| Emergency output | ~20% of normal (about 40W) |
| Emergency duration | 2 hours |
| Battery chemistry | LiFePO4 (lithium iron phosphate) |
| Battery sizing | ~40W × 2 h ≈ 80 Wh usable, with margin |
| Recovery | Automatic recharge and restore on mains return |
| Design standard | IEC 60598-2-22 / EN 1838 (IEC / SANS family) |
Results
- The factory-floor high bays now self-backup on outage — no central emergency system and no separate emergency fittings to maintain.
- The ~20% emergency light (about 40W) keeps the floor navigable and lets low-light work continue through the blackout for the full 2 hours.
- Auto-recovery on mains return holds maintenance for the emergency function at zero across repeated outages.
Related Product
Case Study FAQ
Why dim to 20% instead of full output in emergency?
Holding a 200W high bay at full output from its emergency battery would drain the pack in minutes. Dropping to about 20% (roughly 40W) still delivers the safe-light level needed for evacuation and low-light work on the factory floor, and it is what makes a 2-hour runtime practical from a battery that fits inside the luminaire. The 20% figure is the customer's specified emergency level.
How long does the emergency light last?
Two hours. At roughly 40W for 2 hours the LiFePO4 pack has to deliver about 80 Wh, and we size it with margin so the full 2 hours is still available as the cell ages. The driver holds the reduced output for the whole period rather than fading as the battery discharges.
Does it need a central emergency system?
No. The self-contained drivers make each high bay independent, which is simpler to install across a large factory floor than running a central battery system to every luminaire.
Why LiFePO4 rather than NiCd?
LiFePO4 gives a much longer cycle life, has no memory effect and needs far less routine maintenance than NiCd. That matters here because outages are frequent: the pack is discharged and recharged repeatedly, and LiFePO4 holds its capacity through those cycles instead of needing scheduled replacement. It also avoids cadmium. NiCd still has a place where very low-temperature performance is the binding requirement, but not on this site.
What standard applies for emergency lighting in South Africa?
The emergency driver is built to IEC 60598-2-22 / EN 1838 emergency-lighting criteria. South Africa adopts the IEC / SANS family of standards for luminaires.
Does the luminaire recover automatically after the outage?
Yes. When mains returns the driver recharges the LiFePO4 pack and restores the high bay to normal output on its own.