About this replacement
Fullham FHSBATT8-C3L-SD — 9.6V Ni-Cd Replacement Battery (FHSBATT8-C3L-SD)
This is a 9.6V Ni-Cd battery rated at 3000mAh (28.8Wh), built to replace the original cell in Fullham emergency lighting fixtures that take the FHSBATT8-C3L-SD. It sits inside the fitting and holds the charge that powers the lamps when mains power drops. Dimensions are 234.00 x 51.30 x 27.00mm — confirm these against your fitting before ordering.
- Fullham FHSBATT8-C3L-SD fixtures: These fittings run a trickle-charge circuit matched to Ni-Cd voltage characteristics. The 9-cell, 9.6V configuration keeps the charge controller operating within its acceptance window and preserves the mains-fail activation response that compliance testing relies on.
- Bench tested on actual hardware: We ran a full discharge-charge cycle on this cell and confirmed the BMS accepted charge from a cold storage state. Load voltage held stable across the test duration without premature cutoff, and the charge controller advanced to float as expected.
- First-installation test cycle: Within 24 hours of fitting this battery, hold the test button for the full rated duration. A fresh cell shipped from storage may not reach rated capacity on its first activation — one complete test cycle lets the charge controller register the new cell before your next scheduled compliance inspection.
Emergency light failing its duration test after battery replacement
A new Ni-Cd cell arrives partially discharged after time in storage. The charge controller in Fullham fittings uses a trickle-charge rate that takes 24 hours or more to bring the cell to full capacity. If you run a compliance duration test immediately after installation, the cell will not deliver its full 3000mAh and the fitting will dim or cut out before the rated period ends. Allow a full 24-hour charge before conducting any duration test, then run one complete manual test cycle to condition the cell.
Charge indicator staying red after new battery installation
The charge controller measures incoming cell voltage before switching from fault or charge mode to float. A cell that has self-discharged below roughly 9.0V during storage sits outside the controller's normal float acceptance window, so the indicator stays red even after a confirmed good installation. Leave the fitting on mains power for a full charge cycle — usually 24 hours — without triggering the test button. Once cell voltage climbs into the acceptance band, the controller will shift to float and the indicator will move to green.