Visonic Powermax Pro 9.6V Replacement Battery 0-9912-G

Visonic Powermax Pro Series — 9.6V Ni-MH Replacement Battery (0-9912-G)

This 9.6V 2000mAh Ni-MH cell replaces the internal backup battery in the Visonic Powermax Pro and related control panels, including the Amber Select, AmberLink Emergency Response, and PowerMax Complete. It sits on continuous float charge and takes over when mains power drops, keeping the panel armed and monitoring without interruption.

• Powermax Pro platform fit: The Powermax Pro, Amber Select, and AmberLink panels share the same 9.6V eight-cell NiMH pack format, the same connector footprint, and the same BMS float-charge profile. One cell fits all of them because Visonic standardised the backup bay across this control panel family.
• Bench tested on actual hardware: We cycled this cell through a simulated mains-dropout sequence on a Powermax Pro panel. The BMS accepted the cell, entered float charge within two minutes of reconnection, and the panel cleared its low-battery fault after the full conditioning window completed.
• Post-installation float charge window: Do not run a zone test or trigger a full diagnostic immediately after fitting this cell. The panel BMS requires 24–48 hours on float charge before it will report the battery as healthy. Testing too early will produce a false low-battery warning even on a fully functional new cell.

Alarm panel showing low battery hours after installing new cell

NiMH backup batteries in Visonic panels do not arrive fully charged. The panel BMS measures resting voltage on the pack and compares it against a threshold — typically around 9.0V fully conditioned. A new cell fresh out of packaging often sits below that threshold until the float charger has run for at least 24 hours. The low-battery LED or fault code the panel displays is the BMS doing its job correctly, not a sign of a faulty cell. Leave the panel on mains power for 48 hours and the fault will clear on its own once the pack reaches float voltage.

Alarm losing programming during a power outage after battery swap

If the panel loses its zone programming or reverts to defaults during a mains outage, the backup battery was not yet accepted by the BMS at the time of the outage. The panel needs the battery to hold above approximately 8.4V under load to sustain SRAM and keep programming intact. A cell that has not completed its 48-hour conditioning cycle may drop below that threshold immediately under load. Restore mains power, allow a full 48-hour float charge, then confirm the battery fault LED is clear before treating the installation as complete.