The 1756-EN2T is a high-performance single-port EtherNet/IP communication module built for the Allen‑Bradley ControlLogix chassis platform by Rockwell Automation. It serves as the primary Ethernet gateway between the ControlLogix backplane and the EtherNet/IP industrial network, enabling implicit real-time I/O control, explicit messaging, peer-to-peer tag exchange, HMI connection, motion control, and CIP Safety communication across standard industrial Ethernet infrastructure. This module is the official upgrade replacement for the older 1756-ENBT and remains an active lifecycle product, widely stocked for new system builds, expansion projects and plant spare inventory across all industrial sectors that adopt the NetLinx architecture.

Designed for standard Category 5 twisted-pair cabling, the 1756-EN2T runs auto-negotiating 10/100 Mbps EtherNet/IP and carries one RJ45 copper Ethernet port together with an onboard USB NAP port for local commissioning. Engineers can connect a laptop directly to the NAP port to assign static IP addresses, update module firmware, upload/download program files and run live diagnostics without disrupting the production Ethernet trunk. It supports standard Ethernet topologies including linear, star and DLR Device Level Ring networks, giving system designers flexibility to build fault-tolerant network layouts without switching to dual-port modules such as the 1756-EN2TR.

Connection capacity is one of its key upgrades compared with the legacy ENBT. The 1756-EN2T supports up to 256 CIP connections and 128 TCP connections, which allows it to handle more distributed I/O adapters, variable frequency drives, remote HMIs and third-party EtherNet/IP devices on the same network segment. It supports CIP Sync time synchronization and can manage up to 8 axes of integrated motion over EtherNet/IP, making it suitable for packaging lines, material handling, automated assembly and continuous process applications that require coordinated motion control. The module also supports CIP Safety, permitting mixed safety and standard control traffic over the same EtherNet/IP network when paired with compatible safety controllers and safety I/O nodes.

It fits into any empty single slot inside a standard 1756 ControlLogix chassis, working seamlessly across ControlLogix 5550, 5570 and 5580 controller families, subject to firmware revision matching. The module draws 1 A from the 5.1 VDC backplane with typical power dissipation around 5.1 W; its operating temperature range spans from 0 °C to 60 °C, complying with IEC industrial environmental test standards for shock, vibration and RF immunity, and holding global certifications including UL, CE and ATEX T4 classification. Front-panel LED indicators labeled LINK, NET and OK deliver instant visual status for link activity, network traffic and module health, helping maintenance technicians rapidly isolate faults such as IP conflicts, link loss, backplane communication failures and connection overloads.

Configuration and programming for the 1756-EN2T are completed inside Studio 5000 Logix Designer (formerly RSLogix 5000). Users assign IP settings, configure I/O ownership, set up produced/consumed tags and define message instructions for cross-controller communication. It interoperates with the full Rockwell EtherNet/IP ecosystem, including Flex I/O adapters, Kinetix drives, PanelView HMIs, Stratix industrial switches, and other ControlLogix communication cards such as the 1756-CN2R and 1756-DNB for multi-network integration. When deployed in redundant ControlLogix chassis systems, specific series and firmware revisions are required; Series D hardware supports newer redundancy revisions, while older series units must be validated against the controller redundancy compatibility matrix before commissioning.

Common field use cases for the 1756-EN2T include upgrading aging 1756-ENBT Ethernet cards, adding EtherNet/IP connectivity to existing ControlLogix racks, connecting remote distributed I/O over factory LAN, integrating variable speed drives and motion axes, providing network access for SCADA and HMI clients, and stocking emergency spare modules to reduce downtime. Available inventory includes new factory sealed, surplus open-box and fully tested refurbished units. Refurbished 1756-EN2T modules undergo complete backplane communication testing, EtherNet/IP link and connection load testing, firmware reset and LED verification before shipment. Buyers should always confirm series, firmware compatibility, required connection count and network topology when selecting between 1756-EN2T, dual-port 1756-EN2TR, fiber 1756-EN2F or extreme-temperature 1756-EN2TXT variants.

Key technical highlights of 1756-EN2T:

• Brand: Allen‑Bradley (Rockwell Automation)
• Catalog number: 1756-EN2T
• Product type: EtherNet/IP Communication Module
• Platform: ControlLogix 1756 chassis
• Network interface: Single RJ45 copper port, 10/100 Mbps auto-sensing
• Auxiliary port: USB NAP local programming port
• Max CIP connections: 256
• Max TCP connections: 128
• Motion support: Up to 8 integrated motion axes
• Safety: CIP Safety compliant
• Time sync: CIP Sync
• Backplane current: 1 A @ 5.1 VDC
• Operating temperature: 0 °C to 60 °C
• Configuration software: Studio 5000 Logix Designer
• Mounting: Single-slot installation in any ControlLogix chassis slot
• Lifecycle: Active
• Direct predecessor: 1756-ENBT (discontinued)
• Related variants: 1756-EN2TR, 1756-EN2F, 1756-EN2TXT
• Typical applications: Factory automation, packaging, material handling, process control, motion control, HMI and SCADA networking

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  1756-DNB