Allen-Bradley 1756-EN2T/B EtherNet/IP Bridge Module

Configured for real-time EtherNet/IP communication in ControlLogix architecture, the Allen-Bradley 1756-EN2T/B (1756-EN2T/B EtherNet/IP Bridge Module) provides direct execution of CIP-based data exchange between ControlLogix controllers and Ethernet network nodes. The module interfaces with the 1756 backplane to handle cyclic I/O traffic and explicit messaging across dual RJ-45 ports.

Suffix Breakdown & Model Matrix

• 1756-EN2T: Base EtherNet/IP communication module for ControlLogix chassis integration

• /B Revision: Hardware revision update with internal circuit and communication stack optimization
  No further functional sub-model segmentation is defined in the provided configuration.

Hardware Specifications

ControlLogix EtherNet/IP Backplane Deterministic Network Handling

The module operates within the ControlLogix backplane bus structure, where Ethernet frames are processed through scheduled firmware tasks aligned with controller scan cycles. CIP object routing is executed via embedded communication firmware, enabling deterministic producer-consumer data exchange.

Dual-port architecture supports linear, star, and device-level ring segmentation without external bridging logic. Backplane arbitration defines throughput limits based on slot allocation and chassis communication bandwidth, while firmware revision /B modifies internal packet scheduling behavior for improved cycle stability.

Frequently Asked Questions (FAQ)

Q: Can the 1756-EN2T/B support hot-swap operation in an energized chassis?
A: Yes, the module supports hot insertion and removal in a powered 1756 ControlLogix chassis. Re-enumeration occurs through backplane slot detection.

Q: What is the impact of backplane current draw on chassis design?
A: The module draws approximately 1.0 A at 5 VDC. Total chassis power budget must account for cumulative module loading across all slots.

Q: Does firmware revision mismatch affect CIP communication?
A: Yes, mismatch between controller firmware and module revision may reduce CIP connection availability or block explicit messaging sessions.

Field Installation Guidelines

Insert the module into a compatible 1756 ControlLogix chassis slot with alignment to the backplane connector. Ensure full seating to establish electrical continuity. Use shielded twisted-pair Ethernet cabling with controlled grounding at the switch-side earth reference point. Maintain separation from high-voltage conductors to reduce electromagnetic coupling. Configure IP addressing via BOOTP/DHCP utility or controller-side network configuration prior to runtime operation.