Allen Bradley | 1756-CNBR ControlLogix Series Dual-Port ControlNet Communication Module

Product Description

The 1756-CNBR communication module from Allen Bradley’s ControlLogix series provides high-speed ControlNet connectivity for industrial automation systems. Featuring two redundant ControlNet ports, it ensures reliable communication between controllers and distributed devices. Designed for use in ControlLogix chassis, it supports up to 64 connections and integrates seamlessly with standard and redundant power supplies.

Technical Specifications

• Manufacturer: Allen Bradley

• Product Line: ControlLogix

• Part Number: 1756-CNBR

• Category: PLC Communication Module

• Module Type: ControlNet communication interface

• Weight: 1.00 lbs (0.45 kg)

• Slot Width: Single slot

• Ports: 2 ControlNet ports (redundant)

• Communication Rate: 5 Mbps

• Maximum Connections Supported: 64

• Logix Communication Connections: 40–48 typical

• Maximum Number of Nodes: 99

• Backplane Current Draw:

• 970 mA @ 5.1 VDC

• 1.7 mA @ 24 VDC

• Power Dissipation: 5.5 W max

• Isolation Voltage: 30 V continuous

• Operating Temperature: 0–60 °C (32–140 °F)

• Enclosure Type: Open-style

• Compatible Chassis: 1756-A4, 1756-A7, 1756-A10, 1756-A13, 1756-A17

• Supported Power Supplies:

• Standard: 1756-PA72/C, 1756-PA75/B, 1756-PB72/C, 1756-PB75/B, 1756-PC75/B, 1756-PH75/B

• Redundant: 1756-PA75R, 1756-PB75R, 1756-PSCA2

• Communication Cable: 1786-RG6 quad shield RG6 coaxial cable

Key Features

• Dual redundant ControlNet ports for enhanced reliability.

• Supports up to 64 connections and 99 nodes.

• High-speed 5 Mbps communication rate.

• Compatible with multiple ControlLogix chassis and power supplies.

• Diagnostic LEDs for system and network monitoring.

Application Scenarios

• Distributed control systems requiring ControlNet communication.

• High-reliability automation networks with redundant communication paths.

• Large-scale manufacturing and process control environments.

FAQ

Q: How many ControlNet ports does the 1756-CNBR module provide?   A: It includes two redundant ControlNet ports for reliable communication.

Q: What is the maximum number of nodes supported?  A: The module supports up to 99 nodes on a ControlNet network.

Q: How does this compare to the 1756-CNB module?  A: The 1756-CNBR offers redundant dual ports, while the 1756-CNB provides a single ControlNet port.