1756-CN2 | Allen Bradley | ControlLogix ControlNet Bridge Module

Product Overview

The Allen Bradley 1756-CN2 operates as a high-performance ControlNet bridge module within the ControlLogix ecosystem. This module facilitates deterministic, repeatable data transfers between controllers and I/O devices across a ControlNet network. It manages complex messaging and real-time I/O control with a steady 5 megabit-per-second communication rate. We supply this module in 100% Brand New original condition, ensuring your network architecture maintains maximum data throughput and synchronization.

Technical Specifications

The 1756-CN2 offers expanded node capacity and connection limits compared to standard bridge modules, making it suitable for high-density industrial applications.

Engineering Advantages

• Deterministic Data Control: The 1756-CN2 enforces strict time-critical data management. It ensures that mission-critical I/O updates arrive at precise intervals, eliminating the jitter often found in non-deterministic Ethernet configurations.

• Large-Scale Network Capacity: This module supports up to 99 nodes and 131 simultaneous connections. This high capacity allows engineers to consolidate multiple smaller networks into a single, manageable ControlNet trunk, reducing hardware costs and cabling complexity.

• Low Thermal Footprint: Despite its high processing power, the module dissipates only 19.1 BTU per hour. This efficient thermal design prevents heat accumulation in high-density chassis, protecting neighboring processor or I/O modules from heat-induced failure.

• Simplified Slot Integration: The compact single-slot design fits into any standard 1756 ControlLogix chassis. It draws minimal current from the 24V DC rail, preserving backplane power for high-draw analog or motion modules.

FAQs

• How does the 1756-CN2 handle network configuration?

  You configure the module using RSNetWorx for ControlNet. This software allows you to set the Scheduled Maximum Node (SMAX) and the Network Update Time (NUT), ensuring the 1756-CN2 synchronizes perfectly with other devices on the wire.

• Can I use this module for redundant ControlNet media?

  The 1756-CN2 supports standard ControlNet physical media. For applications requiring media redundancy (Dual RG-6 cables), ensure you use the redundant version of this module or verify your tap configurations to maintain signal integrity during a cable fault.

• Does this unit arrive in factory-sealed packaging?

  Yes. We guarantee that every 1756-CN2 unit is 100% Brand New. It arrives in original Allen Bradley packaging, complete with all factory-issued documentation and high-grade internal components.

• What is the difference between the 1756-CN2 and earlier bridge modules?

  The 1756-CN2 provides significantly higher connection limits (131) and supports more nodes compared to legacy modules like the 1756-CNB. This makes it the preferred choice for modernizing existing ControlLogix systems that require more bandwidth.