Allen-Bradley 1788 DeviceNet Linking Device Modules – 1788-EN2FFR

Technical Dossier

Product Details And Specifications

Allen-Bradley 1788 Series Technical Notes

The Allen-Bradley 1788 series comprises DeviceNet linking devices and communication interface modules engineered for integration between EtherNet/IP networks and DeviceNet field device networks. These modules occupy a critical position in process automation infrastructure across global heavy industries — including petrochemical refineries, nuclear power generation facilities, offshore oil platforms, and large-scale chemical processing plants — where DeviceNet remains the dominant field-level network protocol for sensor and actuator communication.

Installed base for the 1788 series spans hundreds of thousands of nodes worldwide. In facilities where DeviceNet was specified as the standard field bus during the 1990s and 2000s capital build-out cycles, the 1788 linking device is a non-replaceable architectural component. Replacement of the entire field network is cost-prohibitive; therefore, maintaining a reliable supply of 1788 series spare parts is a long-term operational requirement for plant maintenance teams.

The Evolution of 1788 Architecture

The 1788 series was introduced by Rockwell Automation / Allen-Bradley as a bridging solution to connect DeviceNet (IEC 62026-3) field networks to higher-level control and information networks. The architectural evolution of the series reflects the broader transition in industrial networking from proprietary backplane buses to open Ethernet-based protocols.

Early Generation (1788-DNBO / 1788-CN2DN): Initial linking devices focused on ControlNet-to-DeviceNet bridging, enabling DeviceNet field devices to be managed from ControlNet-based PLC backplanes such as the ControlLogix platform. These modules used the UCMM (Unconnected Message Manager) protocol for configuration and explicit messaging.

Mid Generation (EtherNet/IP Integration): As EtherNet/IP became the dominant upper-layer protocol in Rockwell architectures, the 1788 series expanded to include EtherNet/IP-to-DeviceNet linking devices. The 1788-EN2FFR represents this generation — providing a dual-port EtherNet/IP interface with Device Level Ring (DLR) topology support, enabling ring-based network redundancy without additional hardware.

Compatibility Considerations: 1788 linking devices are compatible with RSNetWorx for DeviceNet (configuration software) and integrate with Studio 5000 Logix Designer via Add-On Profiles (AOPs). Firmware compatibility must be verified against the ControlLogix or CompactLogix controller firmware revision in use. Modules running firmware prior to v3.x may not support DLR topology or advanced diagnostic features available in later revisions.

Lifecycle Status: The 1788 series is in the mature/end-of-life phase. Rockwell Automation has issued Product Discontinuation Notices (PDNs) for several 1788 catalog numbers. For facilities still operating DeviceNet infrastructure, long-term maintenance support — including refurbished, tested, and surplus new-in-box units — is the primary procurement strategy.

1788 Full Catalog & Functionalities (SKU List)

EtherNet/IP to DeviceNet Linking Devices:

• 1788-EN2FFR: Dual-port EtherNet/IP to DeviceNet linking device with Device Level Ring (DLR) support; 64-node DeviceNet network capacity.
• 1788-EN2DNR: EtherNet/IP to DeviceNet linking device with embedded switch; supports linear and DLR topologies; 64-node capacity.
• 1788-ENBT: Single-port EtherNet/IP to DeviceNet linking device; 10/100 Mbps; 64-node DeviceNet scanner.
• 1788-EN2DN: Dual-port EtherNet/IP to DeviceNet linking device; embedded 2-port switch; no DLR support.

ControlNet to DeviceNet Linking Devices:

• 1788-CN2DN: ControlNet to DeviceNet linking device; supports scheduled and unscheduled ControlNet connections; 64-node DeviceNet scanner.
• 1788-CN2DNR: ControlNet to DeviceNet linking device with redundant ControlNet media support; dual BNC connectors.
• 1788-CNBR: ControlNet bridge module; used for ControlNet network segmentation and repeating.

DeviceNet Scanner / Adapter Modules:

• 1788-DNBO: DeviceNet bridge/scanner module for use with 1756 ControlLogix backplane via 1756-DNB; legacy configuration.
• 1788-DN: DeviceNet scanner card for use in 1771 PLC-5 I/O chassis; supports up to 63 DeviceNet nodes.
• 1788-DNET: DeviceNet scanner module for SLC 500 platform; 1746 chassis compatible.

Serial / DH+ to DeviceNet Linking Devices:

• 1788-DNBO/A: DeviceNet to DH+ bridge; enables legacy DH+ network devices to communicate with DeviceNet field nodes.
• 1788-SDS: Smart Distributed System (SDS) to DeviceNet gateway; used in legacy Honeywell SDS migration projects.

Power Supply & Ancillary Modules:

• 1788-PKTX: DeviceNet PCMCIA card for laptop-based RSNetWorx configuration; used by field engineers for node commissioning.
• 1788-PKTXD: Dual-channel DeviceNet PCMCIA interface card; supports simultaneous monitoring of two DeviceNet segments.
• 1788-GR6: DeviceNet grounding resistor module; used to establish proper network ground reference in isolated DeviceNet segments.
• 1788-DNPS: Auxiliary DeviceNet power supply tap; provides supplemental 24VDC bus power for high-node-count DeviceNet trunk lines.

Sourcing Hard-to-Find & Obsolete 1788 Series Parts

DriveKNMS supports installed-base sourcing for this series through RFQ review, including model matching, condition checks and documentation requirements before quotation.

Quality Control for the 1788 Range

The 1788 series presents specific quality control challenges due to the complexity of its dual-network bridging architecture. DriveKNMS applies the following test protocols to all 1788 units processed through our facility:

• EtherNet/IP Port Verification: Each EtherNet/IP port is tested for correct MAC address assignment, IP address acquisition via DHCP and static configuration, and CIP connection establishment with a ControlLogix test controller.
• DeviceNet Scanner Functional Test: The DeviceNet scanner is loaded with a test network configuration using RSNetWorx for DeviceNet. A minimum of 8 DeviceNet slave nodes are connected and polled to verify correct I/O data exchange and explicit messaging.
• DLR Topology Test (EN2FFR / EN2DNR): For DLR-capable models, the module is inserted into a live DLR ring and subjected to a ring-break simulation to verify correct beacon-based ring supervisor failover behavior.
• Firmware Revision Audit: All units are inspected for current firmware revision. Units with outdated firmware are upgraded to the latest Rockwell-published revision prior to shipment, unless the customer specifies a particular firmware version for compatibility reasons.
• Thermal Cycling: Units are subjected to a 4-hour thermal cycle between 0°C and 60°C operating range to identify latent component failures consistent with field-aged hardware.