SLC 500

The SLC 500 is Allen-Bradley's modular small logic controller platform, built around two primary bulletin numbers: 1747 for processor and communication components and 1746 for I/O modules, power supplies, and chassis. In the 1747 series, the prefix identifies the component type — for example, 1747-BA designates a lithium battery used for RAM memory retention, while 1747-AENTR is an EtherNet/IP communication module that enables the SLC 500 processor to communicate over EtherNet/IP networks. In the 1746 series, the suffix indicates function: 1746-P3, for instance, is a power supply sized for larger SLC 500 chassis configurations. The platform's modular architecture allows integrators to mix processors, I/O modules, and communication adapters within a common backplane chassis. Buyers selecting SLC 500 components should confirm the bulletin prefix (1747 vs. 1746), the specific suffix code, and compatibility with their installed chassis and processor firmware revision before ordering.