About this replacement
Schneider AN-1441 / BCX1 — 4.8V Ni-MH Replacement Battery (01-2100-507)
This is a 4.8V 230mAh Ni-MH cell for the Schneider Electric AN-1441 and BCX1 programmable logic controllers. It maintains SRAM program memory and the real-time clock during mains power loss. Without a functional cell, a power interruption will wipe the controller's program and lose the RTC timestamp.
- AN-1441 and BCX1 compatibility: Both controllers share the same 4.8V backup rail, connector footprint, and BMS handshake protocol, which is why a single cell — part number 01-2100-507 — covers both platforms. Voltage tolerance on these controllers is tight; fitting a cell outside the 4.5–5.0V window will trigger a battery fault alarm immediately on startup.
- Bench tested on actual hardware: We cycled this cell on a BCX1 test rig and confirmed the BMS accepted the cell without fault codes, float charge engaged within 90 seconds of installation, and SRAM retention held across a simulated 72-hour mains outage.
- Hot-swap procedure on AN-1441 and BCX1: Always replace this battery with the controller powered on and in RUN mode. SRAM on these PLCs has no capacitor backup — if the cell is removed while the controller is off or during a cold swap, the program and RTC data are gone. A full reload from the programming device will be required before the controller can go back into service.
Why the BCX1 battery alarm does not clear after a confirmed good installation
On the BCX1 and AN-1441, the battery fault alarm is latched in firmware — it does not reset automatically when a new cell is fitted. The alarm flag must be manually cleared through the programming software after installation. Navigate to the battery status register in the diagnostics menu and issue a fault reset command. If the alarm re-latches within a few minutes, check that the cell voltage has risen above 4.5V, which can take up to two hours on initial float charge from a storage-depleted state.
New cell reading lower than 4.8V immediately after installation
Ni-MH cells ship at storage voltage, typically 4.2–4.4V, to slow self-discharge in transit. This is normal and does not indicate a faulty cell. The BCX1 float charger will bring the cell up to full rated voltage within one to two hours of the controller being powered. Confirm the charge is progressing by checking the battery voltage register in your programming software — it should read above 4.6V within 30 minutes of installation.