Allen-Bradley 1747-L524 CPU Processor Module SLC 500

The Allen‑Bradley 1747‑L524 CPU Processor Module is a keyless SLC 5/02 central processing unit for the SLC 500 family, designed to sit in a 1747 I/O chassis and control up to 30 local I/O module slots in a single chassis. It is available in two memory configurations: Series A with 1 KB of user memory, and Series B/C with 4 KB of user memory, both using flash-based backup memory. The L524 provides two serial communication ports—DH‑485 and RS‑232—for programming, remote I/O connections, and device networking. Backplane power requirements are 500 mA at 5 V DC and 175 mA at 24 V DC, reflecting its integration with standard 5 V/24 V backplanes in SLC 500 systems. A single local I/O chassis is supported, making this a compact, mid‑range CPU option for discrete control tasks that rely on a mix of 1747 I/O modules. This processor is part of the SLC 500 line’s long-lived legacy, offering straightforward ladder logic programming compatibility while preserving the modularity and ease of maintenance that the 1747 platform is known for.