About this replacement
Thorn Voyager Star LA 2 SBS CON3 200 — 2.4V Ni-MH Replacement Battery (59009425)
This is a 2.4V 4500mAh Ni-MH replacement cell for the Thorn Voyager Star LA 2 SBS CON3 200 emergency lighting unit. It fits the OEM part number 59009425 directly. The battery restores the unit's ability to power its lamp during a mains failure event.
- Star LA 2 SBS CON3 200 fitment: The CON3 200 series uses a 2.4V cell pack with a fixed connector and physical envelope of 92.70 × 36.60 × 18.70mm. The charge controller expects that specific cell voltage range at float — a mismatched cell voltage causes the controller to reject the pack or hold a fault LED.
- Bench tested on actual hardware: We ran this cell through a full charge cycle and a timed load discharge at the rated lamp draw. The BMS accepted the cell without fault, and the charge LED transitioned from red to green within the expected window after reaching float voltage.
- First test cycle after installation: Hold the manual test button for the full rated duration within 24 hours of fitting. This confirms the cell accepts load under actual conditions and allows the charge controller to register the new cell capacity before the next scheduled compliance test.
Charge indicator staying red after new battery installation
A Ni-MH cell shipped from storage will sit at a lower resting voltage than the charge controller's float acceptance threshold. The controller reads this as a fault rather than a depleted cell. Leave the fitting powered on mains for a full 24-hour charge cycle before checking the LED again. If the indicator is still red after 24 hours, measure the cell terminal voltage — it should read above 2.3V at rest.
Emergency light failing its duration test after battery replacement
A new Ni-MH cell does not deliver rated capacity on its first discharge — the cell needs at least one full charge and load cycle to condition the active material. If the unit cuts out before the end of the rated duration test, recharge for a full 24 hours and run the test again. The cell typically reaches rated capacity by the second or third full cycle. Do not log a compliance failure until at least two conditioning cycles are complete.