Allen-Bradley 1747-BA Battery — Detailed Product Introduction

Introduction

In industrial automation, reliable memory retention is essential for preventing data loss, reducing downtime, and protecting production continuity. The Allen-Bradley 1747-BA lithium battery is a critical accessory designed for the Allen-Bradley SLC 500 family of programmable logic controllers (PLCs). Its primary function is to maintain the controller’s volatile memory — including the user program, data tables, and configuration parameters — when power is removed from the PLC.

Although small and often overlooked compared to controllers or I/O modules, the 1747-BA plays a decisive role in keeping operations stable after power failures, planned maintenance shutdowns, or unexpected outages. Without a functional battery, controllers can lose their memory contents, requiring time-consuming reprogramming or restoration from backups. In industries where every minute of downtime carries significant cost implications, having a reliable memory backup solution is not optional — it is mission-critical.

Product Purpose and Role

The 1747-BA battery is engineered specifically for SLC 5/01 through SLC 5/05 processors and other related modules that depend on battery-backed memory. Its role is to supply low-level, continuous DC voltage to the memory circuit, allowing the stored program to persist even when line power is not available.

This battery supports both short-term outages and extended periods of storage. In a typical plant scenario, a controller may be powered down for scheduled maintenance or relocation. With a properly functioning 1747-BA battery, the controller can be powered back up and resume operation exactly where it left off, without the need for reloading programs or retuning process variables.

Design and Key Characteristics

The 1747-BA is designed with industrial reliability in mind. Its lithium chemistry provides several advantages over alkaline or rechargeable solutions, including:

• High Energy Density: Delivers more power in a compact package, supporting longer memory retention periods.

• Stable Discharge Curve: Maintains a consistent voltage output until near the end of its life, reducing the risk of unexpected memory loss.

• Long Shelf Life: Can be stored for years without significant loss of capacity, making it ideal for spare parts inventory.

• Wide Operating Temperature Range: Performs reliably in harsh plant environments, including cold storage or hot equipment rooms.

Additionally, the 1747-BA has been designed for quick and straightforward installation, allowing maintenance personnel to replace batteries with minimal training and minimal system interruption.

Technical Specifications

The table below summarizes the key specifications of the Allen-Bradley 1747-BA battery:

This specification data helps ensure proper battery selection and confirms compatibility with the target controller models.

Installation and Replacement Procedure

Proper installation of the 1747-BA is essential for maintaining program integrity. A typical replacement process involves:

1. Verify Controller Status: If possible, keep the controller powered during battery replacement. This allows memory to remain energized while the battery is disconnected.

2. Remove the Old Battery: Disconnect the existing battery by carefully unplugging it from the battery connector.

3. Install the New Battery: Plug in the new 1747-BA battery, ensuring correct polarity and a secure connection.

4. Check Diagnostics: Many SLC 500 controllers provide battery status indicators or fault codes that can be cleared once the new battery is installed.

Following proper procedure minimizes the risk of program loss and ensures a smooth return to normal operation.

Maintenance and Lifecycle Management

A proactive maintenance plan is recommended for the 1747-BA to avoid unexpected failures. Best practices include:

• Scheduled Replacement: Replace the battery every 2–3 years, or sooner if the controller indicates a low-battery condition.

• Inventory Management: Keep spare batteries in stock, stored in a cool, dry location to maximize shelf life.

• Periodic Testing: During planned downtime, check battery voltage with a meter to confirm it is within acceptable range.

• Documenting Replacement Dates: Maintain a log of battery changes to predict future replacements more accurately.

By integrating battery replacement into routine maintenance schedules, plants can prevent costly program loss incidents.

Application Scenarios

The 1747-BA is widely used across industries such as:

• Manufacturing Plants: Protects programs in assembly line controllers, reducing downtime during power cuts.

• Food and Beverage Production: Ensures critical recipes and batch data remain intact during sanitation shutdowns.

• Utilities and Water Treatment: Supports reliable restart after power outages in municipal infrastructure.

• Warehousing and Material Handling: Prevents loss of conveyor logic and operational parameters.

These application scenarios demonstrate how a relatively inexpensive component can play a major role in keeping production systems stable and efficient.

Benefits of Using the 1747-BA

The advantages of implementing the correct battery solution include:

• Reliable Memory Retention: Protects against accidental data loss, avoiding costly reprogramming.

• Operational Continuity: Facilitates quick restarts after planned or unplanned power interruptions.

• Predictable Maintenance: Known service life allows for proactive replacement schedules.

• Compatibility and Ease of Use: Simple plug-in design, widely supported across the SLC platform.

• Cost-Effective Protection: Prevents production downtime that could cost thousands of dollars per hour.

Safety and Environmental Considerations

Lithium batteries must be handled carefully to prevent short-circuiting, puncture, or exposure to excessive heat. Used 1747-BA batteries should be disposed of according to local regulations, as they are considered hazardous waste in many jurisdictions.

Rockwell Automation’s packaging and documentation provide clear guidelines for safe handling, transportation, and disposal. Recycling programs are recommended where available to minimize environmental impact.

Conclusion

The Allen-Bradley 1747-BA lithium battery is a small but vital part of the SLC 500 ecosystem, ensuring that controller memory remains intact even when primary power is removed. Its robust design, long service life, and ease of installation make it a preferred choice for industrial facilities worldwide.

By implementing a consistent maintenance plan, keeping spares available, and replacing batteries at recommended intervals, users can avoid unplanned downtime and ensure that their automation systems remain reliable for years to come.

Whether in manufacturing, utilities, or process industries, the 1747-BA is an indispensable tool for preserving the integrity of PLC programs and protecting production continuity.