About this replacement
LUPUS XT3 / XT4 — 7.2V Ni-MH Replacement Battery (12189)
This 7.2V 2000mAh Ni-MH cell replaces OEM part 12189 in the LUPUS XT3 and XT4 wireless alarm control panels. It sits on float charge inside the panel and takes over the moment mains power drops, keeping the hub live and monitoring active. Dimensions are 147.00 × 29.00 × 14.50mm — confirm the fit against the tray before installation.
- XT3 and XT4 shared platform: Both panels use the same battery tray, connector pinout, and charge management circuit, which is why a single cell covers both models. The panel's onboard charger applies a constant float voltage — no external conditioning is needed.
- Bench tested on actual hardware: We cycled this cell through simulated mains-loss events and monitored the BMS handshake on both the XT3 and XT4 charge rails. The panel accepted the cell without fault codes on both units after the standard float period.
- Post-installation conditioning for Ni-MH cells: Do not run a zone or siren test immediately after fitting. Allow the panel to float-charge the new cell for 24–48 hours first. Ni-MH cells arrive partially discharged, and the panel's charge monitor will flag a low-battery condition during a test if the cell hasn't reached operating voltage yet.
Alarm panel showing low battery hours after installing a new cell
Ni-MH cells ship at roughly 40–60% state of charge to reduce self-discharge during transit. The LUPUS XT3 and XT4 panels read battery voltage continuously and will trigger a low-battery alert if the cell sits below their threshold — typically around 6.8V under light load. This is not a fault with the cell. The panel needs 24–48 hours on mains power to bring the new cell up to full float voltage before the alert clears. Do not pull the cell and test it on a meter mid-cycle — let the panel's own charger complete the process.
Panel losing zone programming during a power outage after battery swap
If the panel drops its configuration during a mains failure, the replacement cell has not yet been accepted as a valid backup source. The XT3 and XT4 require the battery to hold above approximately 6.6V under backup load to sustain SRAM and radio module power. A cell installed less than 48 hours before an outage may not have enough charge to cover this. Restore mains, allow a full 48-hour float charge, then manually trigger a mains-loss test to confirm the panel holds programming before relying on the backup.