Allen-Bradley 1756-HSC High Speed Counter Module

Allen-Bradley 1756-HSC is a two-channel ControlLogix high-speed counter module designed for precise pulse and encoder counting within a Rockwell Automation backplane. It provides two 24‑bit counter registers, with channel inputs A, B, and Z for each counter, enabling both quadrature counting and index-enabled counting. The digital inputs for A, B, and Z accept 5 V or 12–24 V DC with either single-ended or differential wiring, while four digital outputs offer 5 V DC at 20 mA or 10–30 V DC at 1 A with electronic fusing to signal status or drive signalling logic. The module is a 36‑pin unit that can be installed in local or remote ControlLogix chassis, and it draws backplane current—300 mA at 5 V and 3.0 mA at 24 V. It supports multiple operating modes, including Counter Mode, Encoder x1, Encoder x4, and Frequency Mode, with configuration that can set timing from 0 to 2000 ms in 10 ms steps. Maximum input frequencies are specified as up to 1 MHz for pulse counting, 250 kHz for quadrature counting, and 500 kHz for rate measurement, making it suitable for high-speed encoder applications on conveyors, speed sensing, and indexing tasks in automation systems.