Purchase now: Allen-Bradley 1756-BATM Battery Module
Purchase now: Atlantechdrives provides you the 1756-BATM, a highly specialized, externally mounted battery module engineered by Rockwell Automation to provide extended, ultra-reliable memory backup for legacy ControlLogix programmable automation controllers (PACs). While standard 1756-L6x processors utilize small internal lithium batteries (like the BA1 or BA2) to maintain their volatile RAM during a power outage, these small batteries typically only provide a few weeks of backup power. In major manufacturing facilities, steel mills, or automotive plants that experience extended seasonal shutdowns or prolonged power disconnections, a standard battery will drain completely, resulting in the catastrophic loss of the entire customized PLC program. The 1756-BATM completely solves this critical vulnerability. Designed to mount externally directly adjacent to the ControlLogix chassis, this heavy-duty module houses two massive «D» size lithium battery cells (part number 1756-BATA). By feeding a continuous, highly stable 3.0V DC trickle charge to the processor via a dedicated cable, it dramatically extends the RAM retention lifespan from mere weeks to several months, ensuring your machine boots up flawlessly even after a long-term factory hibernation.
Technical Specifications of the 1756-BATM
The 1756-BATM assembly does not plug directly into the high-speed backplane; it mounts on the cabinet panel or DIN rail next to the chassis and interfaces directly with the front battery port of the designated controller using a specialized bridging cable.
- Part Number: 1756-BATM
- Platform Compatibility: ControlLogix 1756-L6x Series Processors
- Battery Capacity: Houses two 1756-BATA «D» size lithium cells (sold separately)
- Nominal Voltage: 3.0V DC output to the processor
- Mounting: External panel mount (adjacent to the 1756 chassis)
- Function: Massively extended volatile RAM retention during power loss
Expert Tips: The Hot-Swap Procedure and Battery Replacement
When dealing with volatile PLC memory, procedural hygiene is everything. Expert Tip: When the BAT LED on your processor finally illuminates (indicating even the massive D-cells are getting low), you must perform a «hot-swap» battery replacement. Never turn off the main chassis power to change the batteries inside the 1756-BATM. You must leave the ControlLogix chassis completely powered on and actively running the factory. Open the front cover of the externally mounted 1756-BATM, remove the depleted 1756-BATA D-cells, and insert the fresh ones. Because the main 24V or 120V backplane power is actively supplying the processor’s RAM, the memory is totally safe during the physical battery exchange.
Installation Advice: Cable Routing and Strain Relief
The 1756-BATM connects to the front faceplate of the L6 processor via a relatively thin, delicate bridging cable. When installing this module, you must carefully route this cable away from heavy 480V AC motor contactors or high-frequency Variable Frequency Drive (VFD) wiring to prevent electromagnetic interference (EMI), although DC battery lines are generally less susceptible. More importantly, ensure there is absolutely no physical tension or strain on the cable. If the cable is pulled tight and accidentally unplugs from the processor faceplate while the main cabinet power is off, the RAM will wipe instantly, negating the entire purpose of the external battery module.
Frequently Asked Questions (FAQs)
Q: Does the 1756-BATM come with the lithium batteries included in the box?
A: No. The 1756-BATM is just the empty hardware housing and the connection cable. You must purchase the required 1756-BATA lithium D-cell batteries separately to populate the module.
Q: Can I use this extended battery module on a modern 1756-L71 or L81E processor?
A: No. Modern ControlLogix L7 and L8 processors completely eliminated the need for lithium batteries. They utilize a capacitor-based Energy Storage Module (ESM) to instantly write the RAM to a non-volatile SD card during a power failure, making external battery modules obsolete for new architectures.
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This externally mounted battery module provides extended backup life for racks containing multiple ControlLogix 5561 CPUs.
