Allen-Bradley 1786-RPCD ControlNet Dual Coaxial Hub Repeater

Allen-Bradley 1786-RPCD ControlNet Dual Coaxial Hub Repeater Module

Product Overview

The 1786-RPCD is a high-performance ControlNet Coaxial Hub Repeater designed by Rockwell Automation to overcome the physical distance and topology limitations of standard copper segments. By actively regenerating and retiming ControlNet signals, the 1786-RPCD maintains deterministic data integrity across extended cable runs. This module features two BNC coaxial ports, allowing for the creation of star or point-to-point network architectures, which are often more efficient than traditional linear daisy-chains in large-scale industrial facilities. Operating on 24 VDC (integrated via the repeater adapter), it ensures that high-speed communication remains stable across complex distributed I/O and PLC-to-PLC links.

Technical Specifications

The 1786-RPCD is engineered for precision timing and signal amplification within the ControlNet physical layer.

• Manufacturer: Rockwell Automation / Allen-Bradley

• Model Number: 1786-RPCD

• Module Type: Dual Copper Coaxial Repeater

• Network Media: RG-6 Quad-Shield Coaxial Cable

• Impedance: 75 Ω

• Channels: 2 Independent Coaxial Ports

• Connector Type: BNC (Bayonet Neill–Concelman)

• Function: Signal Regeneration, Retiming, and Hub Distribution

• Current Draw: 400 mA @ 5 VDC (from adapter backplane)

• Power Supply: 24 VDC Nominal (provided through 1786-RPA adapter)

• Topologies Supported: Star, Point-to-Point, and Tree architectures

• Operating Temperature: 0°C to +55°C (32°F to 131°F)

• Storage Temperature: -40°C to +85°C (-40°F to +185°F)

• Weight: 0.39 lbs (0.23 kg)

• Certifications: IECEx, CE, UL, CSA, ATEX (Zone 2)

• Lifecycle Status: Discontinued after Dec 30, 2025 (Engineering replacement required)

Core Performance Features

• Signal Regeneration & Retiming: The 1786-RPCD does not simply amplify noise; it cleans and retimes the ControlNet digital signal pulses, preventing the accumulation of jitter that can lead to network scheduling errors.

• Topology Flexibility: Traditional ControlNet is limited to a linear bus. The 1786-RPCD acts as a hub, allowing a single trunk line to branch into two separate directions, significantly reducing total cable length in decentralized systems.

• Deterministic Reliability: By maintaining the strict timing required for Concurrent Time Slot (NUT) scheduling, this repeater ensures that safety-critical data reaches its destination within specified timeframes.

• Hot-Swappable Capability: Designed for high-availability environments, this module can often be serviced within the modular repeater rack without shutting down the entire network segment.