Allen-Bradley 1746-IA8 Eight-Point Input Module

The Allen-Bradley 1746-IA8 Eight-Point Input Module is an eight-channel digital input option for the SLC 500 I/O system. It accepts eight independent 100–120 VAC signals and converts each to a discrete input for the connected processor, with all channels routed through the 1746 backplane. The module occupies a single slot in a 1746 I/O rack and presents its eight inputs as one Input Word (16-bit) to the controller. It’s designed for use with Allen-Bradley SLC 500 controllers and integrates into existing 1746 I/O configurations without changing the central logic. Typical applications include wiring AC-powered field devices such as pushbuttons, limit switches, and sensors into a machine or automation line, enabling straightforward ladder logic or function-block control. When expanding an SLC 500 system that already relies on AC-powered inputs, the 1746-IA8 provides a compact, drop-in path to increase input density while preserving compatibility with the 1746 I/O family and its addressing scheme. Being part of the 1746 IA family, it uses the standard backplane addressing and wiring conventions, enabling seamless integration with existing IA-series modules.