Safe-O-Tronic DS 4.5V Replacement Battery 1200mAh Alkaline

Safe-O-Tronic DS / LS / DS-T — 4.5V Alkaline Replacement Battery (38400200)

This is a 4.5V, 1200mAh alkaline replacement battery for Safe-O-Tronic electronic door locks. It fits the DS, LS, and DS-T models and restores power to the lock mechanism, keypad, and access control functions. Dimensions are 46.20 x 31.50 x 10.70mm — verify fit before installing.

• DS, LS, and DS-T compatibility: All three models run from the same 4.5V flat-pack alkaline cell using the same connector and housing slot. The lock controller draws from a shared voltage rail, so one battery spec covers the full range.
• Bench tested on actual hardware: We ran this battery through the DS lock's power-on cycle and confirmed the BMS accepted the cell without low-voltage warnings. The motor actuated fully and the keypad lit without hesitation.
• Post-swap access verification: After fitting the new battery, test every access method — keypad, Bluetooth, and any keycards — before you close the door. Some DS-series locks run a firmware handshake after a power interruption. If that handshake hasn't completed, the lock may reject credentials even though the motor appears to work.

Why the DS lock beeps a low-battery warning immediately after a fresh battery install

The DS controller samples voltage at power-on and compares it against a stored threshold. Alkaline cells that have sat in a warehouse for months can measure slightly below that threshold even when new. Safe-O-Tronic sets the cutoff conservatively, so a cell at 4.2V or lower can trip the warning before the lock is even used. If the beeping persists, check cell date codes and replace with the freshest available stock — a new cell in spec should present at or above 4.4V at rest.

Bluetooth drops out and won't reconnect after battery replacement

Removing the battery cuts power to the Bluetooth module entirely, and some DS-T firmware versions do not automatically re-advertise after power is restored. The module waits for a manual trigger rather than broadcasting on its own. Remove the battery, wait 10 seconds, reinsert it, then open the lock's companion app and initiate a new pairing scan within 60 seconds of power-on. If the lock still doesn't appear, hold the indoor reset button for 5 seconds to force the module back into pairing mode.