Allen-Bradley

Allen-Bradley 1756-CNB ControlLogix ControlNet Bridge Communication Module

SKU 1756-CNB

In stock
  • 12-month warranty
  • Free returns within 30 days

  • Manufacturer: Allen-Bradley

  • Product No.: 1756-CNB

  • Country of origin:United States

  • Product Type: Communication Module

  • Payment: T/T, Western Union

  • Weight: 350g

  • Dimensions: 14.5 x 11.2 x 3.5 cm

  • Shipping port: Xiamen

  • Warranty: 12 months

Overview

The Allen-Bradley 1756-CNB is a ControlLogix ControlNet bridge communication module for the 1756 platform. It connects a ControlLogix chassis to a ControlNet network.

Rockwell Automation lists the 1756-CNB as discontinued from December 31, 2024. The listed engineering replacement is 1756-CN2.

Technical Specifications

  • Catalog number: 1756-CNB
  • Platform: ControlLogix 1756
  • Communication: ControlNet
  • ControlNet interface: 1 BNC port
  • Maximum connections: 64
  • Backplane current: 970 mA at 5.1 VDC; 1.7 mA at 24 VDC
  • Enclosure: Open style

Lifecycle and Replacement

Lifecycle status: Discontinued.

Discontinued date: December 31, 2024.

Rockwell replacement: 1756-CN2, listed as an engineering replacement.

Check the installed module series, firmware, network schedule, and ControlNet configuration before migration. A replacement module should not be treated as a drop-in change without engineering review.

FAQ

What is the primary function of the Allen-Bradley 1756-CNB?
The 1756-CNB is a ControlNet bridge communication module designed to interface a ControlLogix 1756 chassis to a ControlNet network, enabling scheduled I/O data transfer and unscheduled messaging between controllers and remote devices.

What is the communication rate of the 1756-CNB module?
The 1756-CNB operates at a deterministic communication rate of 5 Mbps on standard ControlNet media.

How many Logix connections does the 1756-CNB support?
The module supports a range of 40 to 48 Logix communication connections, depending on the system configuration and application demands.

Does the 1756-CNB require a dedicated slot in the chassis?
Yes, it mounts into any single slot of a standard 1756 ControlLogix chassis and draws power directly from the backplane.

What software is required to configure the 1756-CNB?
The module is configured and scheduled using RSNetWorx for ControlNet software, typically integrated within the RSLogix 5000 or Studio 5000 environment.

View all FAQs →

Product Documentation

Technical Datasheet (PDF) Complete specifications and technical drawings.

Technical Datasheet

Allen-Bradley 1756-CNB ControlLogix ControlNet Bridge Communication Module

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Global Express Shipping

  • Standard Delivery: 4-6 Business Days via DHL, FedEx, and UPS.
  • Express Dispatch: Same-day dispatch for in-stock orders placed before 2:00 PM (GMT+8).
  • Worldwide Coverage: Serving over 150 countries, including rapid delivery to Saudi Arabia and UAE.

Returns & Warranty

  • 30-Day Guarantee: Returns accepted for in-stock products in original, factory-sealed packaging.
  • 12-Month Warranty: Every industrial component is backed by our professional technical warranty.

Orders are processed and delivered Monday-Friday (excluding public holidays).


For full eligibility, restocking fees, and international return details, please view our official Refund & Return Policy .

TECHNICAL SPECIFICATIONS

Country of origin
United States

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