Allen-Bradley 1756-HSC High Speed Counter Module

The Allen-Bradley 1756-HSC ControlLogix High Speed Counter Module is a two-channel, four-output I/O module designed for fast pulse counting and encoder feedback in ControlLogix systems, featuring two 24‑bit counters with A, B, and Z inputs per channel and a 36‑pin RTB (1756‑TBCH or 1756‑TBS6H) for wiring. It supports 5 V logic or 12/24 V logic inputs, draws about 300 mA from the backplane at 5 V or 3 mA at 24 V, and dissipates up to 3.5 W under load (1.6 W backplane‑only), with isolation of 250 V (input group‑to‑backplane) and 125 V (input group‑to‑input group); each counter is backed by two 24‑bit registers and the module can be configured in Periodic Rate or Continuous Rate modes with selectable rates (0, 1, 2, 4, 8, 16, 32, 64, 128, 256). It also supports high‑speed input frequencies suitable for encoders and timing tasks, with up to 250 kHz for quadrature, 500 kHz for rate measurement, and 1 MHz for pulse counting, making it well suited for encoder feedback on conveyors, spindles, and other fast counting applications.