Allen-Bradley 1756-DNB DeviceNet Communication Module

Allen-Bradley 1756-DNB DeviceNet Communication Module is a single-port DeviceNet bridge/scanner for Rockwell ControlLogix systems, functioning as the DeviceNet master that connects a DeviceNet network to the 1756 backplane. It occupies one slot width in a 1756 chassis and provides a dedicated DeviceNet interface to communicate with devices such as sensors and actuators. The module supports three DeviceNet data rates—125 Kbps, 250 Kbps, and 500 Kbps—with corresponding maximum network distances of 500 m, 250 m, and 100 m, respectively, and it supports up to 64 DeviceNet nodes on the network. It uses a standard 5-pin DeviceNet connector, and CE/low-voltage compliance requires the DeviceNet network to be powered from a SELV or PELV source. On the power side, the DeviceNet portion draws about 60 mA at 24 VDC and the module dissipates roughly 3.5 W total. Configuration and diagnostics are typically performed via RSNetWorx for DeviceNet. The 1756-DNB is documented as the ControlLogix DeviceNet bridge/scanner module, designed to integrate a DeviceNet network with a ControlLogix controller.