Product Description

Model Number Interpretation

• 45C: Unified prefix for Reliance AutoMate 45C series control and interface components.

• 220: Designates a dedicated R-NET communication interface module for AutoMate 20 systems.

• B: Represents the second hardware revision, featuring improved signal integrity, enhanced noise immunity, and more robust circuit protection compared to the original 45C220.

• Hyphen: Optional industrial part-number formatting (45C-220B = 45C220B), with identical functionality and specifications.

Technical Specifications

• Power Supply: 5 VDC (from backplane), 1.2 A typical current consumption.

• Network Protocol: Proprietary R-NET (Reliance Network) token-passing protocol.

• Transmission Media: 75 Ω coaxial cable (BNC connectors), single or dual-cable configuration.

• Network Speed: 1 Mbps maximum data transfer rate.

• Node Capacity: Supports up to 32 AutoMate PLC nodes per R-NET network segment.

• Distance: Maximum 1,000 meters (3,280 ft) per segment with proper cable and termination.

• Operating Temperature: 0°C to 55°C; humidity 20%–90% non-condensing.

• Mounting: DIN-rail or panel mount via AutoMate 20 series backplane.

• Weight: ~1.5 kg (3.3 lbs); rugged metal enclosure for industrial durability.

• Diagnostics: On-board LEDs for network status, activity, and fault indication.

Interface and Communication Configuration

• Network Ports: Two BNC connectors (primary/secondary) for redundant or single R-NET cabling.

• Backplane Interface: Proprietary AutoMate 20 series edge connector for power and data exchange with the host CPU (e.g., 45C20A).

• Status LEDs:

  • PWR: On when 5 VDC backplane power is present.

  • NET OK: On when the R-NET network is operational and synchronized.

  • TX/RX: Flashes during data transmission/reception.

  • FAULT: On for network errors (e.g., cable break, termination fault, node conflict).

• Termination: Built-in 75 Ω termination resistor, enabled via DIP switch for end-of-line nodes.

Core Functions

• R-NET Network Management: Acts as a master or slave node to manage token passing, data routing, and synchronization across the network.

• High-Speed Data Exchange: Transfers I/O status, register data, and program commands between PLCs at 1 Mbps, supporting real-time coordinated control.

• Network Redundancy: Supports dual-cable R-NET configurations for fault-tolerant communication in critical applications.

• CPU Offloading: Handles all R-NET communication tasks independently, reducing the main CPU’s workload and improving scan time efficiency.

• Fault Detection and Reporting: Monitors network health continuously, with LED indicators and diagnostic codes for quick troubleshooting of cable, termination, or node issues.

Application Scenarios

• Legacy AutoMate 20 Network Systems: Direct replacement or upgrade for aging 45C220 interface modules in multi-PLC manufacturing lines.

• Distributed Industrial Control: Used in automotive assembly, packaging, and material handling systems requiring coordinated control across multiple zones.

• Process Automation Networks: Deployed in water treatment, pharmaceutical, and food & beverage plants to link PLCs controlling pumps, valves, and production equipment.

• Retrofit Projects: Ideal for expanding or modernizing older AutoMate 20 systems without full hardware replacement, preserving existing investments.

• Redundant Communication Systems: Applied in critical processes (e.g., power utilities, chemical processing) where network uptime is essential.

Usage and Maintenance Instructions

• Installation: Insert the module into an available slot on the AutoMate 20 backplane, ensuring secure connection; set the DIP switch for termination if the module is an end node.

• Wiring: Connect 75 Ω coaxial cable to the BNC ports, following R-NET network topology rules (linear or star); avoid sharp bends and ensure proper grounding.

• Power-On Check: Apply power to the backplane; confirm the PWR and NET OK LEDs are on, with no FAULT indication.

• Routine Maintenance: Quarterly inspections; clean dust from BNC connectors and enclosure; check cable tightness and termination switch setting; verify LED status during operation.

• Safety: Disconnect all AC power to the backplane and wait 5 minutes for discharge before servicing; avoid live maintenance; use only 75 Ω R-NET-compatible coaxial cables and connectors.