The Allen-Bradley 1756-EN2TR is a dual-port EtherNet/IP communication module used in the ControlLogix PLC system from Rockwell Automation. It provides high-speed industrial Ethernet communication and supports Device Level Ring (DLR) redundancy, making it suitable for high-availability automation networks.
Compared with the 1756-EN2T, the EN2TR includes two Ethernet ports, enabling ring topology and network redundancy.
It is widely used in manufacturing, process automation, power systems, and large distributed control architectures.
Technical Specifications
| Parameter | Details |
|---|---|
| Product Type | EtherNet/IP Communication Module |
| Model | 1756-EN2TR |
| System Compatibility | Allen-Bradley ControlLogix |
| Network Type | EtherNet/IP |
| Communication Speed | 10/100 Mbps |
| Ethernet Ports | 2 × RJ45 (Copper) |
| Topology Support | Linear, Star, Device Level Ring (DLR) |
| Protocols | EtherNet/IP, TCP/IP |
| Max TCP Connections | 128 |
| Max CIP Connections | 256 |
| Redundancy Support | Yes (DLR network redundancy) |
| Backplane Interface | ControlLogix chassis backplane |
| Power Consumption | ~5.1 W |
| Current Draw | ~1 A @ 5.1 V DC |
| Isolation Voltage | 30 V continuous |
| Installation Type | Chassis slot-mounted module |
| Operating Temperature | 0°C to 60°C |
The EN2TR supports Device Level Ring (DLR), which allows network recovery in milliseconds if a link fails.
Physical Dimensions & Weight
- Dimensions (H × W × D): 145 mm × 35 mm × 140 mm
- Weight: ~0.3–0.5 kg
Designed as a single-slot ControlLogix module for standard industrial control cabinets.
Function in ControlLogix System
The 1756-EN2TR is used to:
- Connect ControlLogix controllers to EtherNet/IP networks
- Support Device Level Ring (DLR) topology for redundancy
- Enable real-time I/O and messaging communication
- Communicate with PLCs, HMIs, SCADA, drives, and remote I/O
- Improve network availability in critical systems
Recommended Related Models
- Allen-Bradley 1756-EN2T (single-port Ethernet module)
- Allen-Bradley 1756-EN2F (fiber Ethernet module)
- Allen-Bradley 1756-EN3TR (higher performance Ethernet module)
- Allen-Bradley 1756-CNB / CN2 ControlNet modules
- Allen-Bradley 1756-L7x / L8x ControlLogix controllers
