About this replacement
DSC PowerG PG9911 Siren — 3.6V Li-MnO2 Replacement Battery (BATT13036V)
This 3.6V Li-MnO2 cell replaces the internal battery in the DSC PowerG PG9911 wireless siren, including PGX901 and PGX911 variants. Rated at 14500mAh (52.2Wh), it supports the long standby draws and infrequent high-current bursts that a self-contained siren requires. The chemistry is lithium manganese dioxide — not lithium-ion — which holds voltage flat across extended standby periods.
- PowerG PG9911, PGX901, PGX911 platform fit: These sirens share the same battery bay dimensions, connector orientation, and BMS handshake. The 60.25 × 35.16 × 33.50mm cell slots directly into each housing without modification, and the system panel recognises the new cell over the PowerG RF link once charge stabilises.
- Bench tested on actual hardware: We cycled the cell through simulated standby loads and repeated siren trigger pulses. The BMS held voltage above 3.3V through repeated high-current bursts, and the panel cleared the low-battery fault flag within 36 hours of float charge on a live system.
- PowerG siren battery swap timing: Do not run a zone test or trigger the siren immediately after fitting this cell. Allow 24–48 hours on the system before any diagnostic test — the panel reads battery state via the RF link, and a cell that hasn't fully stabilised will return a false low-battery report during the test cycle.
Why the PG9911 siren stays silent on a test trigger after a battery swap
The PG9911 siren runs an internal charge-stabilisation window after a new cell is fitted. During this window — typically 30 to 60 seconds from first power — the siren will not respond to a trigger command from the panel. This is intentional: the BMS blocks output until the cell voltage settles above the minimum activation threshold. If the test fires during that window, the siren logs no fault but produces no sound. Wait at least 60 seconds after closing the housing before sending a test signal from the panel.
Alarm panel showing low battery hours after installing a new cell
Li-MnO2 cells ship at a partial open-circuit voltage — typically around 3.4V — not the 3.6V nominal the panel expects at full charge. The PowerG panel polls the siren's battery state via RF and compares it against a stored threshold. If the cell hasn't reached float equilibrium, the panel flags low battery even though the cell is new. This clears on its own once the system has run for 24–48 hours. No reset is needed — monitor the panel at the 48-hour mark and confirm the fault flag has cleared.