Panasonic A06B PLC Compatible Battery 3V 1800mAh Li-MnO2

Panasonic A06B / FP2-C2 / IC963 — 3V Li-MnO2 Replacement Battery

This 3V, 1800mAh lithium manganese dioxide cell replaces the backup battery in Panasonic A06B, FP2-C2, and IC963 PLC systems. It powers the real-time clock and SRAM memory retention circuit, keeping program data and system time intact during mains power interruptions or scheduled maintenance. Voltage and capacity match the original cell specification exactly.

• A06B, FP2-C2, and IC963 compatibility: All three controllers share the same 3V lithium backup architecture and use an identical cell footprint. The SRAM retention circuit draws from this cell continuously whenever mains power is absent, so voltage stability under micro-current load matters more than peak output.
• Bench tested on actual hardware: We ran this cell on a live A06B controller and confirmed the BMS float charge accepted the cell without a fault condition. SRAM contents remained intact across a simulated mains-drop cycle at ambient temperature.
• Hot-swap procedure for this controller family: Always replace this battery with the PLC powered on and in RUN mode. Removing the cell while the controller is powered off will immediately erase SRAM contents — the controller cannot retain program data without either mains power or a live backup cell present. If the PLC was off during the swap, reload the program from your programming device before attempting a restart.

Why the A06B loses program memory during a battery swap

The A06B holds its ladder logic and parameter data in SRAM, which requires a continuous supply voltage to retain its contents. When both mains power and the backup cell are absent at the same time — even briefly — the SRAM collapses and the program is gone. This is not a fault with the battery or the controller. It is a fundamental property of volatile memory. The only recovery path is a full program reload from a connected programming device.

Battery alarm not clearing after a confirmed good installation

Fitting a new cell does not automatically reset the battery alarm on Panasonic PLC platforms. The alarm flag is written to a status register and must be cleared manually through the programming software — the controller does not poll the cell voltage on its own after a swap event. Open the diagnostic or status screen in your programming environment, locate the battery alarm bit, and reset it explicitly. If the alarm returns within 24 hours, check enclosure temperature — a warm cabinet significantly accelerates self-discharge on Li-MnO2 cells and can shorten service intervals.