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Allen Bradley ControlLogix Communication Modules

Communication Modules

Available options include EtherNet/IP, ControlNet, DeviceNet, Data Highway Plus, Remote I/O, Foundation Fieldbus, Serial, DH-485, and SynchLink. Multiple communication modules can be installed in the ControlLogix system to allow control and/or sharing of data over different networks.

After determining the networks you will be using you will be able to select the communication modules your system will require and the necessary cables and network equipment. Remember to plan for extra modules and cables if you are designing a redundant system. It is possible to route a message through up to 4 different chassis (8 communication hops). A ControlLogix controller is not required in each chassis to accomplish this. The following tables list the various communication modules available to interface with your system. The first table lists normal usage applications for the industry protocol communications networks.

Communication Network Applications

Communication NetworkStandard Applications
EtherNet/IPPlant Management (Material Handling)
Configuration,Data Collection & Control/Single High Speed Network
Time Critical Applications/No Established Schedule
Inclusion of Commercial Technologies (Video over IP, etc.)
Internet/Intranet Connection
Integrated CIP Motion & Safety
ControlNetHigh Speed Transfer of Time Critical Data Between Controllers and I/O Devices
Deterministic & Repeatable Data Delivery
Media Redundancy
Intrinsic Safety
Redundant Controller Systems
DeviceNetConnection of Low-Level Devices to Controllers w/o Interfacing Through I/O Modules
Data Sent As Needed
More Diagnostics for Improved Data Collection & Fault Detection
Less Wiring & Reduced Start-Up Time than Traditional Hard-Wired System
Data Highway PlusPlant Wide and Cell Level Data Sharing With Program Maintenance
Data Sent on Regular Basis
Transferring Information Between Controllers
Remote I/OConnections Between Controllers & I/O Adapters
Data Sent on Regular Basis
Distributed Control/Each Controller Has I/O & Communicates with Supervisory Controller
Foundation FieldbusFieldbus Transmitters & Actuators
Closed Loop Control
Process Automation

EtherNet/IP Communication Modules

The EtherNet Industrial Protocol Network (EtherNet/IP) is an industry standard open network which supports both real time input/output messaging and message exchange. EtherNet/IP uses readily available standard EtherNet communication chips and/or physical media.

Part NumberEtherNet/IP
CIP Motion
Axes (Max)
1756-EN2F Bridge, FiberFiber100 Mbps8128256
1756-EN2T Bridge, CopperCopper10/100 Mbps8128256
1756-EN2TRBridge, Copper,
Embedded Switch
Dual Copper10/100 Mbps8128256
1756-EN3TRBridge, Copper,
Embedded Switch
Dual Copper10/100 Mbps128128256
1756-ENBTBridge, CopperCopper10/100 Mbps64128
1756-EWEBWeb Server ModuleCopper10/100 Mbps64128
1756-EN2TXTControlLogix-XT Bridge, Copper, Extreme EnvironmentsCopper10/100 Mbps8128256

EtherNet/IP Network Accessories

Part NumberEtherNet/IP ApplicationSpecifications
1585J-M8PBJM-xRJ45 Patchcord; x = 2 (2m), x = 5 (5m),
or x = 10 (10m)
8 Conductor, Teal Riser PVC Cable
(Flex Rated Cable Available)
1585J-M8CC-HRJ45 Insulation Displacement
Connector (IDC)
0.128... 0.325 mm2  (26... 22 AWG), Cat. 6,
IDC, No Tool Required
1585J-M8CC-CRJ45 Crimp Connector With Boot,
Quantity: 50 Pieces
0.128... 0.205 mm2 (26... 24 AWG), Cat 5e,
Crimp Tool Required
1585JcrimpCrimp ToolUse With 1585J-M8CC-C
9300-RADESRemote Access Dial-In Kit56 Kbps Modem Connection With:
Pre-Configured Modem,
Communication Module,
DIN Rail Mounting Hardware,
and Associated Cables

ControlNet Communication Modules

The ControlNet network provides high speed capabilities by combining the best aspects of an input/output network and a peer-to-peer network. ControlNet features deterministic, repeatable transfers of critical control data. The modules with 128 Logix connections also have an additional 3 connections reserved for redundant control. For the modules with 64 Logix connections it is recommended to use only 40 to 48 of these for input/output connections.

Part NumberControlNet
of Nodes
1756-CN2/BStandard Media Bridge5 Mbps128 (+3)99
1756-CN2R/BRedundant Media Bridge5 Mbps128 (+3)99
1756-CNBStandard Media Bridge5 Mbps6499
1756-CNBRRedundant Media Bridge5 Mbps6499
1756-CN2RXTControlLogix-XT Redundant Media Bridge5 Mbps128 (+3)99

DeviceNet Communication Module and Accessories

The DeviceNet network, as its name implies, provides communication connections between system devices. The devices can be as simple as sensors and actuators or more complex devices, such as controllers and computers.

Part NumberDeviceNet Application
1756-DNBDeviceNet Bridge Module
Communication Rates: 125 Kbps (500 m max); 250 Kbps (250 m max);
500 Kbps (100 m max)
Number of Nodes: 64
KwikLink Lite Flat MediaNewer, ODVA approved for wiring DeviceNet networks. Supports intermixing of  DeviceNet cable types, such as round with flat. KwikLink Lite connectors provide insulation displacement.
KwikLink Flat MediaModular cabling with flat 4-wire cable and insulation displacement connectors (IDCs). System Nodes can be added without cutting or stripping trunkline. Eliminates need for predetermined cable lengths.
Round MediaRound trunk cable is available in bulk spools or as pre-molded cable sets of various lengths. Round cable supports rugged and durable DeviceNet components, including stainless steel versions:
1. Thick trunk round cable provides maximum length DeviceNet trunk lines.
2. Thin trunk cable reduces maximum trunk line distances with a more compact installation. Thin cable outer jacket is TPE for added chemical resistance.

Data Highway Plus and Remote Input/Output Communication Modules and Accessories

Part NumberDescriptionCommunication
1756-DHRIODH+/Remote I/O57.6 Kbps, 115.2 Kbps, 230.4 Kbps32 DH+ messages per DH+ ModuleRemote I/O Scanner:
32 logical rack /channel;
16 block-transfer/channel
1756-RIORemote I/O57.6 Kbps, 115.2 Kbps, 230.4 Kbps--Remote I/O Scanner/Adapter:
32 physical racks (0... 76), any rack size and/or block transfers
10 Scheduled
1756-DHRIOXTExtended Temperature
DH+/Remote I/O
57.6 Kbps, 115.2 Kbps, 230.4 Kbps32 DH+ messages per DH+ ModuleRemote I/O Scanner:
32 logical rack/channel;
16 block-transfer/channel
1770-CDBelden 9463 twin axial cable; connects communication module to DH+ Network
9300-RADKITRemote access dial-in kit: 56 Kbps modem connection to DH+ Network devices. Kit includes: Pre-configured Modem, Communication Module, DIN rail mounting hardware, and associated cables.

FOUNDATION Fieldbus Linking Devices

FOUNDATION Fieldbus networks are designed for distributed control of process applications. The Fieldbus network is linked to other plant networks with the following bridge devices. Although these linking devices can accommodate up to 16 devices per H1 link, 8 to 10 devices per link is recommended.

Part NumberFieldbus
H1 PortsDevices per
H1 Link
Total Device Links
Network Bridge
Fieldbus: 31.25 Kbps
EtherNet/IP: 10/100 Mbps
Network Bridge
Fieldbus: 31.25 Kbps
EtherNet/IP: 10/100 Mbps
1757-FFLDC2 ControlNet
Network Bridge
Fieldbus: 31.25 Kbps
ControlNet: 5 Mbps
1757-FFLDC4 ControlNet
Network Bridge
Fieldbus: 31.25 Kbps
ControlNet: 5 Mbps


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