Allen-Bradley 1771-OAD PLC-5 8-Point Output Module

The Allen-Bradley 1771-OAD PLC-5 digital output module is a 16-point AC output card for PLC-5 backplanes, designed to switch 12–120 V AC discrete loads directly from a PLC-5 program. It provides 16 independently switched outputs, each capable of delivering up to 2 A, for a total module current rating of 8 A. Rated for standard PLC-5 operating conditions, it enables compact, high-density control of relays, contactors, and other AC loads across an automation rack. The OAD variant is part of the 1771 I/O family and plugs into the PLC-5 backplane, receiving control signals from the processor to energize individual outputs with predictable timing. Typical applications include machine controls, conveyors, pumps, and fans where multiple AC devices must be switched under programmatic control, all without external interface modules. The module operates on a nominal 120 V AC supply, with a voltage range that accommodates typical industrial power fluctuations, and it adheres to the PLC-5 family’s discrete-output voltage requirements, ensuring compatibility with existing I/O wiring and field devices. For designers upgrading legacy PLC-5 systems or expanding I/O, the 1771-OAD provides a high-density solution that preserves familiar ladder logic with expanded output capacity, helping optimize cabinet space and wiring complexity while maintaining reliable digital control of AC loads.