Allen-Bradley 1756-CNB ControlNet Communications Module

The Allen-Bradley 1756-CNB ControlNet Communications Module is a ControlNet bridge module for Rockwell Automation's ControlLogix platform, delivering a dedicated ControlNet interface that connects a ControlNet network to a 1756 backplane in ControlLogix systems and enables scalable network expansion across multiple racks and remote I/O. Powered directly from the ControlLogix backplane, it enables deterministic data exchange between ControlNet devices and the Logix processor by bridging ControlNet traffic to remote I/O racks, routing status and I/O data, and supporting efficient integration with the broader automation architecture. Firmware revision F 11.003 is associated with this hardware listing, indicating the specific feature set and compatibility for this generation of the module within contemporary ControlLogix configurations. Typical applications include integrating remote ControlNet I/O into a ControlLogix process control system, bridging legacy ControlNet devices with modern Logix controllers, and enabling distributed, time‑deterministic communications across ControlNet networks in manufacturing, packaging, and process automation environments.