Purchase now: Allen-Bradley 1756-EN2F Fiber Ethernet Bridge
Purchase now: Atlantechdrives provides you the 1756-EN2F, a high-performance, industrial-grade EtherNet/IP fiber optic communication bridge engineered by Rockwell Automation for the robust ControlLogix 1756 platform. While standard copper Ethernet networks are sufficient for localized control cabinets, the 1756-EN2F is specifically designed for sprawling industrial facilities where distance and severe electromagnetic interference (EMI) present massive challenges. Utilizing 100Base-FX multimode fiber optic technology, this communication module allows the ControlLogix chassis to interface with remote distributed I/O racks, HMIs, Variable Frequency Drives (VFDs), and other PACs over distances of up to 2 kilometers (1.24 miles) without the need for intermediate switches or repeaters. Because fiber optic cables transmit data via light rather than electrical currents, the 1756-EN2F provides absolute immunity against ground loops, high-voltage spikes, radio frequency interference (RFI), and heavy magnetic fields generated by large industrial motors and welding robots. It is the premier networking choice for steel mills, water treatment plants, and massive chemical processing facilities.
Technical Specifications of the 1756-EN2F
The 1756-EN2F operates at 100 Mbps (Fast Ethernet) and supports advanced network topologies, including star, tree, and linear configurations. It provides massive bandwidth capabilities to handle highly demanding control, safety, and motion data simultaneously across the plant floor.
- Part Number: 1756-EN2F
- Platform: ControlLogix 1756 System
- Network Protocol: EtherNet/IP
- Media Type: 100Base-FX (Multimode Fiber Optic)
- Connector Type: LC (Lucent Connector)
- Maximum Cable Distance: 2 km (with 50/125 μm or 62.5/125 μm multimode fiber)
- Communication Capacity: Supports up to 128 TCP/IP connections and 256 CIP connections
- Backplane Current Draw: 1.2 A at 5.1V DC
Expert Installation Advice: Fiber Optic Handling and LC Connectors
Working with fiber optics requires a significantly higher level of physical care than standard copper Cat5e/Cat6 cables. Expert Tip: The 1756-EN2F utilizes industry-standard LC duplex connectors. The golden rule of fiber optic installation is absolute cleanliness. Before inserting the fiber patch cord into the 1756-EN2F module, you must meticulously clean the LC connector ferrules using a specialized lint-free fiber optic cleaning pen or wipes with 99% isopropyl alcohol. A single speck of microscopic dust on the fiber core can severely attenuate the light signal, causing packet loss, intermittent network drops, and critical IO faults. Furthermore, strictly observe the minimum bend radius of your fiber optic cables inside the control cabinet; bending the cable too sharply will cause light to leak out of the cladding, immediately breaking network communication.
Advanced Configuration: CIP Sync and Multicast Management
The 1756-EN2F is not just a simple network switch; it is a highly intelligent CIP (Common Industrial Protocol) bridge. It fully supports CIP Sync (IEEE 1588 Precision Time Protocol), allowing for microsecond-level synchronization across the fiber network, which is an absolute requirement for distributed CIP Motion applications. When configuring this module in Studio 5000, engineers must carefully manage their Unicast and Multicast connections. By default, newer Logix firmwares prefer Unicast connections to reduce unnecessary network broadcast traffic. However, if you are integrating legacy devices or producing consumed tags to multiple listening chassis simultaneously, ensure your network infrastructure supports IGMP Snooping to prevent the fiber network from being flooded by Multicast data packets.
Frequently Asked Questions (FAQs)
Q: How do I assign an IP address to a brand new 1756-EN2F module?
A: Out of the box, the module is set to BOOTP/DHCP mode. You must use Rockwell’s BOOTP-DHCP Server utility software via the network, or you can use the physical rotary switches on the front of the module to assign a static IP address between 192.168.1.1 and 192.168.1.254.
Q: Can the 1756-EN2F be used in a ControlLogix Redundancy system?
A: Yes. The 1756-EN2F is fully compatible with ControlLogix redundancy systems, allowing you to build highly available, fault-tolerant fiber optic networks where a primary chassis can seamlessly failover to a secondary chassis without losing network connectivity.
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To achieve high-speed fiber optic networking in harsh EMI environments, connect this bridge to a Stratix managed switch.
