Allen‑Bradley 1747‑L552 SLC 5/05 PLC Processor

1747-L552 is Rockwell Allen‑Bradley SLC 500 series SLC 5/05 rack-mounted CPU processor, equipped with 32K words battery-backed memory and dual built-in communication ports (10Base-T Ethernet + RS232). It serves as the core logic controller for medium discrete and small process automation equipment, executing ladder logic programs, scanning local SLC 1746 series I/O modules, and delivering real-time control signals to field actuators.

This legacy modular CPU supports online editing and remote network programming, compatible with RSLogix 500 programming software. It features a three-position key switch for RUN/PROG/REM mode switching and multi-status LED fault indicators. Discontinued original production, it is a mainstream aftermarket spare for upgrading and maintaining traditional SLC 500 automation production lines.

Main Specifications

• Brand: Allen‑Bradley (Rockwell Automation); Model: 1747-L552; Series: SLC 500 SLC 5/05 CPU
• Memory: 32K total words (28K program/data + 4K dedicated data storage), lithium battery data backup
• Onboard Interfaces: 10Mbps 10Base-T Ethernet port, RS232 serial port (DH485/DF1/ASCII protocols)
• I/O Capacity: Max 4096 digital input + 4096 digital output points, up to 480 analog I/O channels
• Scan Speed: Typical 0.9ms per 1K program words, 0.225ms typical I/O scan cycle
• Mode Control: 3-position physical key switch: RUN / PROG / REM remote mode
• Operating Environment: 0℃ ~ +60℃, humidity 5%–95% RH non-condensing, UL & CE certified
• Power Draw: Powered via SLC chassis backplane, single-slot rack installation
• Matching Hardware: 1746 series digital/analog I/O modules, 1747-P1 power supply, PanelView HMI terminals

Core Functions

• Execute ladder logic control programs, handling sequential logic, PID closed-loop regulation, safety interlock and equipment fault judgment tasks.
• Built-in Ethernet TCP/IP communication supports program upload/download, online editing, peer-to-peer data exchange with other SLC 5/05 and PLC‑5 controllers.
• RS232 serial port connects programming laptops, barcode scanners and weighing instruments, supporting DF1 serial communication and local debugging.
• Front panel multi-color LED indicators display RUN, Ethernet link, hardware fault, battery low and force status for rapid on-site troubleshooting.
• Lithium battery retains RAM program and data during power outage, avoiding complete program loss after power failure.
• Standard SLC 500 rack bus definition enables direct plug-and-play replacement without rewiring cabinet terminals or reconfiguring I/O mapping.

Application Scenarios

• Main CPU spare replacement for packaging machinery, food production and logistics palletizing SLC 500 automation control cabinets.
• Medium-sized discrete control spare parts for automotive auxiliary assembly lines, textile winding and metal processing equipment.
• Maintenance backup inventory for water treatment stations, HVAC central control and small chemical batch production workshops.
• Matching master processor cooperating with 1746 analog/digital I/O modules and local HMI touch screens for on-site monitoring.
• Retrofit replacement components for aging SLC 500 systems without native Ethernet communication and insufficient program memory.

• Global aftermarket spare stock for discrete manufacturing factories maintaining legacy Rockwell SLC 500 automation hardware.