Allen-Bradley 1794-VHSC Very High Speed Counter

Allen-Bradley 1794-VHSC is a FLEX I/O two‑channel Very High Speed Counter module for the 1794 FLEX I/O system. It accepts 12–24 V DC signals from encoders, pulse generators, mechanical limit switches, or proximity sensors and returns the count or frequency to the controller in binary form. In counter mode, Channel B provides direction while Channel A carries the pulse; in quadrature encoder mode the unit can count two‑phase signals (X1) for bidirectional operation, with a maximum input frequency of up to 1 MHz per channel and a 24‑bit count range (0–16,777,215) per channel. The module is powered from the FLEX I/O supply (12–24 V DC) and is designed for high‑speed, high‑resolution counting in demanding automation tasks.