The Allen-Bradley 1756-BA1 is a lithium backup battery module used in the ControlLogix PLC system from Rockwell Automation. It provides memory backup power for certain ControlLogix processors, ensuring that critical data such as user programs, controller state, and real-time clock information are retained during power loss.
This battery is not used to power the PLC during operation—it only maintains volatile memory and system data integrity when the controller is switched off or experiences power interruption.
Key Function
- Maintains controller memory during power loss
- Preserves real-time clock and diagnostic data
- Supports program retention in specific ControlLogix CPUs
- Prevents loss of configuration in legacy Series A controllers
Technical Specifications
| Parameter | Details |
|---|---|
| Product Type | Lithium Battery Assembly |
| Model | 1756-BA1 |
| System Compatibility | Allen-Bradley ControlLogix |
| Battery Chemistry | Lithium |
| Nominal Voltage | 3 V DC |
| Capacity | ~1800 mAh |
| Function | Memory backup for PLC controllers |
| Compatible Controllers | 1756-L61 / L62 / L63 (Series A), others |
| Installation Type | Plug-in / wired connector |
| Operating Temperature | -40°C to 60°C |
| Storage Temperature | ~30°C recommended |
The battery is designed for long shelf life and stable operation in industrial environments.
Physical Dimensions & Weight
| Specification | Value |
|---|---|
| Dimensions | ~20 × 24 × 8 mm (cell level) |
| Weight | ~17 g (cell) / ~1.1 kg (assembly variants listed in packaging data) |
(Some listings show higher shipping weight due to protective housing and assembly packaging.)
Where It Is Used
The 1756-BA1 is used in:
- ControlLogix PLC controllers (Series A platforms)
- Industrial automation systems requiring non-volatile memory retention
- Process control systems in manufacturing plants
- Oil & gas and power generation control panels
Role in ControlLogix System
Inside a ControlLogix PLC system, the battery:
- Powers SRAM memory backup circuits
- Maintains controller state during shutdown
- Protects configuration data in older CPU architectures
- Helps prevent re-download of programs after power loss
Modern ControlLogix CPUs often use non-volatile memory (Flash/SD) instead, but the 1756-BA1 is still common in legacy systems.
