Product Overview

The Allen-Bradley 1747-BA​ is a critical lithium memory backup battery designed to preserve the program and data in the volatile memory of Allen-Bradley SLC 500 series programmable logic controllers (PLCs), specifically the SLC 5/03, SLC 5/04, and SLC 5/05 processors. This “aftermarket” designation indicates a high-quality, functionally equivalent replacement battery manufactured to meet or exceed the original specifications of the genuine Allen-Bradley component, offered as a reliable and cost-effective alternative for maintenance and lifecycle support. The primary function of the Allen-Bradley 1747-BA Aftermarket Battery​ is to provide a continuous, low-current power source to the processor’s RAM (Random Access Memory) when the main system power is removed. This prevents the loss of the user-created ladder logic program, variable data table values, and system configuration, which are essential for the machine’s operation. Without a functional battery, a power outage would result in a complete memory wipe, requiring a time-consuming and potentially costly program download from a backup, if one exists.This 3.6V Lithium Thionyl Chloride battery is engineered for long service life and stable voltage output, which is crucial for reliable memory retention over extended periods. The aftermarket version of the 1747-BA​ is constructed with the same physical form factor and electrical characteristics as the original, ensuring a direct, drop-in replacement that connects seamlessly to the battery connector on the SLC processor. Its value proposition is significant for facilities with a large installed base of SLC 500 controllers, as it provides a dependable means of preventing catastrophic data loss at a reduced total cost of ownership. Proactive, scheduled replacement of the Allen-Bradley 1747-BA Aftermarket Battery​ is a cornerstone of preventive maintenance for SLC 500 systems, safeguarding against unexpected production downtime and protecting the intellectual property embedded in the PLC program. It is a small component with an outsized role in maintaining system integrity and operational continuity.

Technical Specifications

Main Features and Advantages

Guaranteed Compatibility and Reliable Performance: A high-quality aftermarket 1747-BA​ battery is designed for guaranteed electrical and mechanical compatibility. It provides the exact 3.6V DC output required by the SLC processor’s memory circuit and features the correct 2-pin connector for a secure, plug-and-play installation. These batteries utilize high-grade Lithium Thionyl Chloride chemistry, known for its excellent energy density, long shelf life, and stable discharge curve. This ensures a consistent voltage supply to the memory chips over the battery’s entire service life, preventing data corruption that can occur with declining voltage from inferior cells. A reliable aftermarket Allen-Bradley 1747-BA​ will offer a capacity that meets or exceeds the original, providing the same or greater backup duration to protect your program during extended power outages or equipment storage.Extended Service Life and Cost-Effectiveness: Premium aftermarket batteries are engineered for longevity. With a typical service life of 3-5 years at room temperature, they match the performance expectations of the OEM part. This allows for predictable, scheduled maintenance, where the battery is replaced during a planned shutdown, eliminating the risk of an unexpected failure. The most significant advantage is cost-effectiveness. Aftermarket versions of the 1747-BA​ are typically available at a fraction of the cost of the OEM-branded battery, allowing facilities to maintain all their SLC 500 controllers proactively without a significant parts budget impact. This makes it economically feasible to implement a plant-wide battery replacement program, which is a best practice for preventing downtime.