About this replacement
Texecom Odyssey Extended Life Siren Alarm — 7.2V Ni-MH Replacement Battery (GP250BVH6A6)
This is a 7.2V, 600mAh Ni-MH replacement battery for the Texecom Odyssey Extended Life Siren Alarm and compatible Odyssey Bell Box Sounders. It matches OEM part numbers GP250BVH6A6 and BAT001. When the original cell depletes after years of standby service, this battery restores the siren's backup power so it can sound during a mains outage.
- Odyssey Bell Box compatibility: The Odyssey Extended Life Siren and Odyssey Bell Box Sounders share the same 7.2V Ni-MH cell format, connector type, and BMS charge circuit. One battery fits across the range without modification.
- Bench tested on actual hardware: We ran this cell on a Texecom alarm circuit and confirmed the BMS accepted the charge profile without fault flags. Voltage held stable at 7.2V nominal across the full charge cycle.
- Float charge conditioning before first test: Do not run a zone test immediately after fitting this battery. Allow 24–48 hours on float charge first. The panel reads cell voltage continuously — a partially charged Ni-MH cell will trigger a low-battery fault even if the battery itself is healthy.
Why the Odyssey siren stays silent on alarm after a battery swap
After fitting a fresh Ni-MH cell, some Odyssey units will not sound immediately on a triggered alarm. The siren's internal circuit holds off activation for 30–60 seconds while it stabilises charge from the new battery. This is normal behaviour — it is not a wiring fault or a failed battery. If the siren still does not sound after a full 48-hour charge period, check that the tamper switch is fully seated and the lid is closed correctly before investigating further.
Panel still reporting low battery 10 minutes after fitting a new cell
The Texecom panel samples backup battery voltage on a timed cycle, not instantly on power-up. A brand-new Ni-MH cell arrives partially discharged from storage — typically reading 6.8–7.0V rather than the 7.2V nominal the panel expects. The panel will continue to report low battery until the cell reaches full float charge, which takes 24–48 hours connected to the alarm's trickle circuit. If the fault clears by the 48-hour mark, the battery and circuit are functioning correctly.