Product Overview

The Allen‑Bradley 1747‑BA is the original memory backup lithium battery for the SLC 500 PLC platform from Rockwell Automation. This plug‑and‑play battery assembly is designed to preserve processor RAM data, ladder logic programs and real‑time clock settings when the main chassis power is shut down or interrupted. For legacy SLC installations, battery failure is one of the most common causes of unexpected program loss, downtime and costly reprogramming work. Installing genuine or fully tested replacement 1747‑BA units helps machine owners and maintenance teams avoid sudden data corruption on packaging lines, conveyor systems, water treatment skids and other equipment running SLC controllers. It comes pre‑wired with the correct matching connector for direct fit into SLC 500 processors.

Key Specifications

• Part Number: 1747‑BA
• Manufacturer: Allen‑Bradley (Rockwell Automation)
• Series: SLC 500
• Battery Cell: FDK CR14250SE, 1/2 AA cylindrical lithium cell
• Nominal Voltage: 3 VDC
• Chemistry: Lithium metal, non‑rechargeable primary battery
• Connector: Factory‑attached 2‑pin plug connector
• Country of Origin: Japan
• Storage Temperature: -40 °C to +85 °C
• Operating Ambient Range: Suitable for standard industrial control cabinet environments
• Typical Installed Service Life: 2 to 5 years, subject to temperature and power cycle frequency
• Uninstalled Shelf Life: Up to approximately 10 years under proper cool, dry storage
• Certifications: CE, UL, UN38.3 lithium battery compliance
• Compatible Programming Software: RSLogix 500

Core Function

The primary purpose of the 1747‑BA is RAM retention. When plant power drops, this battery supplies the tiny standby current required to keep the processor memory alive. SLC 5/03, 5/04 and 5/05 processors feature an internal capacitor that maintains memory for roughly 30 minutes during battery swapping, so technicians can replace the 1747‑BA without immediately losing the running program if the swap is completed within that window. This feature is extremely valuable during scheduled maintenance shutdowns. Without a working backup battery, all logic, tag data and clock values stored in volatile RAM will be erased once power is removed.

Compatibility List

The 1747‑BA fits most modular and fixed SLC 500 processors, including: 1747‑L20, 1747‑L30, 1747‑L40, 1747‑L511, 1747‑L514, 1747‑L524, 1747‑L531, 1747‑L541, 1747‑L542, 1747‑L551 and other SLC 5/01, 5/02, 5/03, 5/04, 5/05 controllers. It is widely stocked as a standard spare for all SLC‑based automation racks paired with discrete I/O, analog modules, HMIs and drives. Before ordering, confirm your processor battery socket requirement, as other Rockwell platforms such as MicroLogix, ControlLogix use different battery part numbers and cannot substitute for 1747‑BA.

Application Scenarios

This backup battery is a must‑have spare for factories still running legacy SLC 500 control systems. It is heavily used in equipment maintenance, retrofit projects, planned shutdown service and emergency spare kits. Typical industries include food and beverage packaging, material handling conveyors, metal fabrication machinery, wastewater treatment, cement plants, printing machines and custom automated machinery. System integrators and automation distributors regularly keep batches of 1747‑BA to support their installed base of aging SLC controllers, as end users aim to extend machine lifecycles before full platform migration to CompactLogix.

Product Supply & Replacement Notes

We supply fully inspected 1747‑BA units. Each battery is visually verified for intact insulation, correct connector and no leakage signs before packing and shipment. Lithium batteries require proper packaging for international freight, and we follow UN38.3 shipping requirements for overseas delivery. Since the SLC 500 series is end‑of‑life, original stock availability fluctuates quickly. If you need bulk quantities or combined shipment with other SLC modules like processors, power supplies and I/O cards, send your inquiry with quantity and target lead time. We recommend proactive battery replacement on a scheduled maintenance schedule rather than waiting for low‑battery alarms or program loss.

Frequently Asked Questions

Q: Is 1747‑BA rechargeable? A: No. It is a primary lithium battery and cannot be recharged. It must be replaced once depleted.

Q: Can I swap the battery without losing my PLC program? A: For SLC 5/03, 5/04 and 5/05 processors, the internal capacitor holds memory for about 30 minutes, allowing safe replacement if finished within that window. Older fixed processors have shorter hold times.

Q: Will 1747‑BA work for ControlLogix or MicroLogix controllers? A: No. 1747‑BA is exclusive to the SLC 500 family. ControlLogix uses 1756‑BA series batteries, while MicroLogix uses separate backup battery assemblies.

Q: What signs show that the 1747‑BA needs replacement? A: Common symptoms include low battery warning on the processor LED, clock reset after power cycling, occasional memory corruption or program missing after shutdown.

Why Buy 1747‑BA From Us

We focus on legacy Allen‑Bradley SLC 500 spare parts for global industrial buyers. We understand that many factories cannot afford unexpected PLC program loss caused by dead backup batteries. We provide clear product photos, proper lithium battery packaging, fast quotation and reliable worldwide shipping. If you need installation guides, datasheets or cross reference checks before purchase, our team can provide supporting documents for your maintenance planning.

1747-L551