Allen-Bradley 1746-OW4 SLC 500 Relay Output Module

The Allen-Bradley 1746-OW4 SLC 500 Relay Output Module is a four-channel relay contact output card for the SLC 500 family, designed to switch external loads through four relay contacts. As an AC/DC relay output module, it supports general-purpose discrete control for devices such as solenoids, relays, indicator lights, or other field devices in industrial automation. The card is intended for installation in an SLC 500 chassis and is driven by the backplane from the processor, energizing each relay to close or open its corresponding field connection. Each channel provides a separate relay contact, enabling independent control of multiple loads while keeping the load side isolated from the controller side. The 1746-OW4's place in the SLC 500 repertoire makes it a common choice for legacy automation projects where robust electromechanical switching is required, with standard wiring practices for discrete outputs and compatibility with the broader 1746 I/O modules family. Applications include machine control, conveyor systems, and batch manufacturing lines where simple, rugged relay switching is favored over solid-state options.