Allen-Bradley PLC-5 1785-L80B CPU Control Processor Module

Product Overview

The Allen-Bradley 1785-L80B is a high-performance programmable logic controller processor within the legacy PLC-5 platform. It serves as the central processing engine designed to orchestrate complex industrial automation architectures by integrating local, extended-local, and remote I/O subsystems into a unified control network. This processor delivers advanced memory capability, robust diagnostic feedback, and multi-protocol connectivity to manage demanding manufacturing and process control applications.

Key Technical Attributes and Functionality

• Processing and Memory CapacityThe module features a substantial memory capacity designed for extensive ladder logic programs and complex data storage requirements. It efficiently manages large-scale input and output configurations, ensuring low scan times and reliable system execution.
• Versatile Communication InterfaceThe controller is equipped with four highly configurable communication ports designated as Channels 1A, 1B, 2A, and 2B. These ports can be independently programmed to function as Data Highway Plus (DH+) interfaces, Remote I/O (RIO) scanners, or Remote I/O adapters, providing flexible topology options for plant-wide networking.
• Peripheral ConnectivityAn isolated 25-pin RS-232C serial port, identified as Channel 0, supports point-to-point communication. This port accommodates standard DF1 full-duplex or half-duplex protocols, ASCII messaging, and DH-485 networks, allowing direct connection to programming terminals, human-machine interfaces (HMIs), and third-party serial devices.
• Real-Time DiagnosticsThe front panel integrates dedicated LED status indicators, including processor status (PROC), I/O forces active (FORCE), and communication activity (COMM). These indicators allow field technicians to conduct rapid visual troubleshooting and monitor system health in real time.

Technical Specifications

• Manufacturer: Allen-Bradley / Rockwell Automation
• Product Line: PLC-5 System
• Model Identification: 1785-L80B
• Hardware Type: Central Processing Unit (CPU) Module
• Onboard Communication Channels: 4 Channels (DH+, RIO Scanner/Adapter) plus 1 Serial Port (RS-232C)
• Physical Dimensions: 4.8 cm x 15.2 cm x 27.3 cm
• Net Weight: 1.32 kg
• Harmonized System Code (HS Code): 8537101190

Industrial Applications

• Automotive assembly lines requiring high-speed peer-to-peer data synchronization.
• Chemical processing facilities demanding extensive remote I/O management.
• Water and wastewater treatment infrastructure utilizing localized DH+ networks.
• Legacy control system migrations and spare parts replenishment for plant lifecycle extension.