About this replacement
Ceag SEB 8/8L — 4.8V Ni-CD Replacement Battery (21147701000)
This is a 4.8V 8000mAh nickel-cadmium replacement cell for the Ceag SEB 8/8L emergency lighting unit. It fits the OEM part numbers 21147701000 and 0108349. The SEB 8/8L is a maintained or non-maintained emergency luminaire used in commercial and industrial facilities where backup lighting must meet duration requirements under local safety codes.
- SEB 8/8L cell compatibility: The SEB 8/8L charge controller expects a 4.8V Ni-CD pack at a specific float voltage range. Swapping in a cell outside that range causes the controller to misread state of charge. This pack matches the original voltage and connector layout so the controller tracks charge correctly from the first cycle.
- Bench tested on actual hardware: We ran this cell through a full charge cycle and a loaded discharge test. The BMS accepted the cell without fault codes, and terminal voltage held steady under the luminaire's draw load throughout the test duration.
- First test cycle after installation: Within 24 hours of fitting, hold the manual test button for the full rated duration. This confirms the new cell accepts load and lets the charge controller register the new cell capacity before your next scheduled compliance inspection.
Emergency light failing its duration test after battery replacement
A freshly installed Ni-CD cell rarely ships at full charge. Storage time, shipping temperature, and the self-discharge rate of Ni-CD chemistry all reduce capacity before the cell reaches the fitting. If you run a compliance duration test immediately after installation, the cell will not yet be at rated capacity and the light will cut out early. Allow a minimum 24-hour charge on the fitting before the first test. After that conditioning period, the cell should deliver its rated 8000mAh load and sustain the luminaire for the full required duration.
Charge indicator staying red after new battery installation
The SEB 8/8L charge controller checks incoming cell voltage before switching from fault or charge state to a green ready indication. A cell that has dropped below the controller's float acceptance window during storage will register as a fault rather than a charge-in-progress state. Leave the fitting powered on mains for at least 24 hours — the trickle charge will bring the resting cell voltage up into the acceptance window. If the indicator has not moved to green after 24 hours, check that the cell connector is fully seated and that the terminal voltage at the pack reads at least 4.2V with a multimeter.