Allen-Bradley 1747-L542 SLC 500 Processor Module

Allen‑Bradley 1747-L542 is a SLC 500 modular CPU designed for the SLC 5/04 controller, delivering 32K words of memory for program and data storage and offering both an RS232 serial port for direct programming and a DH+ (Data Highway Plus) port for networking with remote I/O and other controllers. As a member of the 1747 processor family, this module plugs into a 1747 backplane and executes ladder logic programs created with RSLogix 500, making it suitable for compact, discrete control, sequencing, and machine-control tasks on small to mid-sized manufacturing lines where a legacy PLC solution remains appropriate. The 1747-L542 is documented in Rockwell Automation’s SLC 500 documentation as a 5/04 series processor, with compatibility references to other 1747‑L54x processors and associated memory modules.