About this replacement
Jablotron JA-100 Signal Repeater — 4.8V Ni-MH Replacement Battery (BAT-4V8-N900)
This 4.8V, 2000mAh Ni-MH cell replaces the internal backup battery in the Jablotron JA-100 Signal Repeater and compatible JA-100 wireless elements. The repeater sits between the control panel and remote sensors, extending radio range across the protected site. When this cell depletes, the repeater loses its backup power and signal coverage drops — particularly in areas already at the edge of radio range.
- JA-100 Series compatibility: The JA-100 Signal Repeater and JA-100 wireless elements share the same 4.8V voltage rail, connector footprint, and charge management circuit. OEM part numbers BAT-4V8-N900 and 0102-230 both cross-reference to this cell configuration.
- Bench tested on actual hardware: We cycled this cell through the JA-100 charge circuit and confirmed the BMS accepted the Ni-MH chemistry without fault. Charge acceptance was normal from the first cycle, and the panel cleared its low-battery flag within 24 hours of float charge.
- Post-install conditioning on the JA-100: Do not run a zone or signal test immediately after swapping this cell. Allow 24–48 hours on the panel's trickle charge before triggering any diagnostic. The JA-100 charge circuit needs that window to bring the Ni-MH cell to full float voltage — testing before then can produce a false low-battery report.
Why the JA-100 Repeater still shows low battery hours after a new cell is fitted
The JA-100 panel samples backup battery voltage on a timed cycle — not instantly after power-up. A freshly installed Ni-MH cell sits below full charge voltage at rest, so the first sample often returns a low-battery flag even with a new cell in place. The charge circuit needs 24–48 hours of continuous trickle charge to bring the cell to its full float voltage of around 5.5–5.8V across the pack. Only after that point does the panel's battery check return a clean status. If the fault clears within 48 hours, the cell and circuit are both working correctly.
Alarm programming lost during a mains outage after battery replacement
If the panel loses its configuration during a power cut shortly after a battery swap, the replacement cell had not yet reached sufficient charge to sustain the panel through the outage. A Ni-MH cell straight from storage holds a partial charge — typically 60–70% — not the full capacity the panel relies on for backup. The JA-100 requires the cell to be at full float before it can carry the panel through a mains failure. Restore mains power, allow 48 hours of conditioning, then confirm battery status on the panel before the next outage window.