Allen-Bradley 1746-HT Programmable Logic Controller Module

Allen-Bradley 1746-HT is a SLC 500 high-speed counter/encoder interface module that plugs into a 1746 backplane in an SLC 500 rack to translate fast encoder pulse streams into PLC-count data for precise motion and position feedback. Designed for use with Allen-Bradley SLC 500 controllers, it communicates via the backplane to deliver real-time counts and status to the CPU, enabling high-speed counting and encoder interfacing for motion-related applications. The module draws power directly from the backplane, typically around 200 mA at 5 V, so no external power supply is required for its internal logic. Installation involves placing the 1746-HT in a 1746 rack slot and connecting encoder or pulse input signals to the module’s inputs, where the PLC can access the resulting counts through standard SLC 500 backplane communication.