About this replacement
DOTLUX EXITtop 3679-1 3H — 6.2V LiFePO4 Replacement Battery (300154)
This is a 6.2V 1800mAh LiFePO4 replacement cell for the DOTLUX EXITtop 3679-1 3H emergency exit light fitting. It matches OEM part number 300154 and slots directly into the 3H-rated version of this fixture. Voltage, connector, and cell format match the original specification.
- EXITtop 3679-1 3H compatibility: The 3H suffix identifies the three-hour rated duration version of this fitting. That rating ties directly to cell capacity — the charge controller in this fixture expects a 1800mAh LiFePO4 cell to deliver the full rated illumination period across its discharge curve. Swapping in a different chemistry or lower capacity breaks compliance.
- Bench tested on actual hardware: We cycled this cell through a simulated mains-fail event and monitored BMS cutoff behaviour at end-of-discharge. The charge controller accepted the cell, completed the float charge cycle, and the fault LED cleared without manual intervention.
- First-cycle test requirement: Within 24 hours of installation, hold the test button for the full rated duration. This puts the new cell through one complete discharge so the charge controller can register actual capacity before your next scheduled compliance inspection.
Emergency light failing its duration test after battery replacement
A freshly installed LiFePO4 cell often ships at a partial state of charge after storage. When the fitting runs its duration test immediately, the cell hasn't yet completed a full charge cycle inside the unit, so available capacity is lower than rated. The 3679-1 3H is rated for three hours at full load — a cell at 70% charge on first test will fall short of that window. Allow the fitting to charge for at least 24 hours on mains before running the compliance test, and confirm the charge indicator has moved to green before initiating.
Charge indicator staying red after confirmed good installation
The charge controller in the EXITtop 3679-1 uses resting cell voltage to determine whether it will enter the float acceptance window. A cell that has self-discharged during storage may present a voltage low enough to sit outside that window, causing the controller to flag a fault rather than begin charging. Leave the fitting on mains power for two to four hours — most LiFePO4 controllers will retry the acceptance check once resting voltage climbs above the threshold, typically around 5.8V. If the indicator stays red beyond four hours, measure cell voltage at the connector; a reading below 5.5V indicates the cell requires a pre-charge step before the controller will accept it.