Allen-Bradley 1747-L541 SLC 5/04 PLC CPU Module

Allen-Bradley 1747-L541 SLC 5/04 CPU Module is a 16K-memory processor for the SLC 500 modular controller family, designed to run ladder logic in small to mid-size control applications. It provides a DH+ communications port for Data Highway Plus networks and an RS-232 serial port for programming or device communication, and it is a chassis-mount CPU that plugs into a 1747 backplane in a SLC 500 rack. The processor stores 16K words of user memory and delivers a program scan time around 0.9 milliseconds per keyword, enabling responsive execution of control logic for sequencing, I/O control, and alarm handling. Rockwell Automation lists the 1747-L541 as discontinued as of December 31, 2021, so availability may be limited to remaining stock or used units. This model is part of the SLC 5/04 family (alongside 1747-L542 and 1747-L543 variants) and is commonly found in legacy systems requiring DH+ connectivity and RS-232 programming interfaces.