Allen-Bradley 1747-L524 SLC 5/02 PLC CPU Module

Allen-Bradley 1747-L524 is the SLC 5/02 CPU module for the Rockwell Automation SLC 500 family, delivering ladder-logic processing with 4 KB of user memory in the common Series B/C configuration (Series A uses 1 KB). It includes native RS-232 serial communication and a DH-485 port for networked PLC devices, enabling straightforward programming and remote I/O interaction in small to mid-size control panels. The memory backing for the CPU varies by revision, with Rockwell literature listing EEPROM/UVPROM options in some configurations and other sources noting Flash or battery-backed RAM in different series; for Series B/C the 4 KB memory is standard, while Series A ships with 1 KB. The CPU is chassis-mountable within an SLC 500 rack and draws roughly 0.5 A at 5 V (and 0.175 A at 24 V) when the back-up RAM option is used. Firmware support for Series C starts with OS302 or higher, per 1747-IN010 documentation, while earlier revisions use earlier OS versions. The 1747-L524 provides a compact, cost-effective control solution for discrete manufacturing tasks, machine control, and small automation loops that require reliable SLC 500 compatibility and simple DH-485/RS-232 communications.