Allen-Bradley 1756-IB32 DC Input Module for ControlLogix

The Allen-Bradley 1756-IB32 is a ControlLogix digital DC input module that provides 32 sink-type 24 VDC input points across two 16‑point groups designed for use on a 1756 backplane. It accepts a 10–31.2 VDC input range (nominal 24 V) and wires via removable terminal blocks (1756‑TBCH or 1756‑TBS6H) to the 36‑pin backplane interface. Each channel sinks field current to the backplane, with a backplane current draw of 120 mA at 5.1 V and 2 mA at 24 V, and a module power dissipation up to 6.2 W at 60 °C (0.66 W backplane power). Electrical specs per channel include an on‑state current of 4.8–5.5 mA across the 10–31.2 V range, and an off‑state current up to 2.27 mA with off‑state voltage not exceeding 5 V; input impedance is about 5.67 kΩ. Input timing comprises a hardware delay of up to 380 μs from Off‑to‑On, plus an optional filter of 0, 1, or 2 ms; for On‑to‑Off, a hardware delay of up to 420 μs plus an optional filter of 0, 1, 2, 9, or 18 ms. The 32 inputs are arranged in two 16‑channel groups, making dense I/O layouts straightforward for ControlLogix applications. This module is used to read multiple digital sensors and switches in automation systems, offering reliable, isolated DC inputs within a single 1756 chassis.