Allen-Bradley 1756-OW16I Digital Relay Module

The Allen-Bradley 1756-OW16I is a ControlLogix 16-point digital relay module that provides isolated relay outputs for backplane I/O in a 1756 I/O rack. This module delivers 16 isolated relay outputs and uses a 36-pin removable terminal block for field wiring, enabling clean, channel-by-channel connections. It is designed for use with Rockwell Automation's ControlLogix systems and plugs into 1756-series I/O backplanes, allowing you to switch discrete loads from your PLC program.

Per-channel isolation minimizes electrical interference and cross-talk between circuits, while the module's firmware supports version 3.003, with Rockwell offering that firmware on compatible units. The OW16I is documented as a 16-channel digital relay output module, confirming its role in controlling loads via relay contacts rather than solid-state I/O.

In practical applications, the OW16I is employed to drive discrete field devices from a ControlLogix system, providing galvanic isolation per channel for safety and troubleshooting convenience. The 36-pin terminal block simplifies wiring, and the isolated relays support independent channel operation, making this module well-suited for automation projects that require reliable relay switching managed by PLC logic.