Chassis-based Communication Modules

Our ControlLogix® system uses connections to establish communication links between devices. Our Bulletin 1756 Chassis-based communication modules help make those connections and implement network-based access control for users, devices, and networks in the 1756 chassis. We offer a variety of modules that support EtherNet/IP, DeviceNet, ControlNet, and other network protocols.


1756 EtherNet/IP Communication Modules

  • Offers CIP Security protocol via EN4TR and EN4TRXT communication modules
  • Provides real-time I/O messaging and message exchange
  • Uses off-the-shelf Ethernet communication chips and physical media
  • Supports 128 or 256 Logix connections
  • Offers embedded switch technology capabilities
  • Supports extreme environments via ControlLogix-XT™ communication modules
  • Offers secure connectivity from the control system to upper level systems, programming terminals, and other ControlLogix controllers using the secure communications module
  • Provides Device Level Ring (DLR) connectivity to allow devices to form a ring topology to provide resiliency
  • Offers Parallel Redundancy Protocol (PRP) support for a completely redundant network infrastructure

1756 DeviceNet Communication Modules

  • Uses the Common Industrial Protocol (CIP) to control, configure, and collect data for industrial devices
  • Provides connections between simple industrial devices (sensors and actuators) and higher-level devices (controllers and computers)
  • Supports 64 nodes

1756 ControlNet Communication Modules

  • Uses the Common Industrial Protocol (CIP) to combine the functionality of an I/O network and a peer-to-peer network that provides high-speed performance for both functions
  • Provides open, control network for real-time, high-throughput applications
  • Offers deterministic, repeatable transfers of all mission-critical control data
  • Supports transfers of non-time-critical data
  • Supports 64 or 128 Logix connections and 99 nodes
  • Offers extreme environment support

1756 Data Highway Plus™ and Remote I/O Communication Modules

  • Supports messaging between devices
  • The remote I/O link connects to remote I/O chassis and other intelligent devices
  • Remote I/O functionality enables the module to act as a scanner for transferring digital and block-transfer data to and from remote I/O devices
  • Supports 32 Logix connections
  • Support messaging between devices on DH+™ network

1756 DH-485 Communication Modules

  • Allows the controller to send and receive messages to and from other controllers on the DH-485 network
  • Includes remote programming and monitoring via the Studio 5000™ environment

1756 SynchLink™ Communication Modules

  • Provides time synchronization and data broadcasting for distributed motion and coordinated drive control
  • Connects a ControlLogix chassis to a SynchLink fiber-optic communication link
  • Allows the controller to consume motion axes data from a controller in another chassis

Conformal Coating

Conformal coating is now available on select ControlLogix® products to help protect your automation systems from hostile and harsh environments. Rockwell Automation tested these products for the equivalent of 10 years in an ISA G3 Group A classified environment. These products are identified by the "K" suffix in the catalog number and they

  • Help to protect circuitry against exposure to pollution, moisture, temperature variation, salt spray, organic attack (fungus), and aggressive chemicals and vapors
  • Offer improved product life cycle when exposed to corrosive environments by maintaining long-term surface insulation resistance (SIR) ensuring operational integrity of the assembly

4-Way Redundant Intelligent Fieldbus Junction Box

Additional Information

Industrial Automation and Control Systems — Our systems help provide the integration of control and information across the enterprise that enables our customers to optimize their operations by connecting the plant, site, facility, and people.

Product Selection


  • CE
  • ControlNet International
  • CSA
  • cULus
  • DeviceNet
  • EAC
  • EtherNet/IP
  • Ex
  • FM
  • IECEx
  • KC
  • RCM

Note: Certifications vary by communication module type. See publication 1756-TD003 for details.

Looking for Additional Information?

To find additional product information including CAD drawing files, 3D models and more use our Product Catalog.



Resource Publication Number Language
1756 ControlLogix Communication Modules Specifications Technical Data 1756-TD003
EtherNet/IP Secure Communication User Manual ENET-UM003
ControlLogix System User Manual 1756-UM001
DeviceNet Network Configuration User Manual DNET-UM004
ControlLogix DH-485 Communication Module User Manual 1756-UM532
ControlLogix Data Highway Plus-Remote I/O Communication Interface Module User Manual 1756-UM514
ControlLogix SynchLink Module User Manual 1756-UM521
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