Product Details
Related Product Model Recommendations
Payment & Delivery

FAQs

Q1: What is the primary function of the 1756-EN2TR?
The 1756-EN2TR is a dual-port EtherNet/IP communication module for ControlLogix controllers. It performs the same functions as the 1756-EN2T but adds support for Device Level Ring (DLR) topology, providing single-fault tolerant network redundancy .
Q2: What is DLR and why is it important?
DLR (Device Level Ring) is a network topology that allows devices to be connected in a ring. If a cable breaks or a device fails, the network automatically redirects traffic through the alternate path, ensuring continuous communication. The 1756-EN2TR can act as a ring supervisor or ring node in a DLR network .
Q3: Is the 1756-EN2TR still recommended for new projects?
No. Rockwell Automation lists the 1756-EN2TR as Active Mature, meaning it is still available and supported, but not recommended for new projects. The official successor is the 1756-EN4TR, which offers gigabit speeds, more connections, motion support, and built-in CIP Security .
Q4: What are the maximum connections supported?
The 1756-EN2TR supports up to 128 TCP connections and 256 CIP connections .
Q5: Can I replace a 1756-EN2TR with a 1756-EN4TR directly?
In most cases, yes. The 1756-EN4TR is a drop-in replacement for the EN2TR in most applications. However, exceptions include: ControlLogix 5570 controllers requiring SIL2 safety certification, redundant chassis pairs (only EN2 series is officially certified), and projects with strict firmware version matching requirements.