Allen-Bradley 1756-IB16IFK Fast Isolated Input Module

Allen-Bradley 1756-IB16IFK is a 16-channel ControlLogix digital input module featuring fast isolated inputs with conformal coating for harsh environments. It accepts DC input signals in the 10–30 V range, with a nominal 24 V DC level, and supports both sinking and sourcing configurations. Each of the 16 inputs is independently isolated from the backplane and from other channels, providing protection from ground differentials and cross-talk in industrial environments. The module is specified as a fast input device with an off-to-on propagation delay of 14 µs (nominal) and 23 µs (max), plus a user-configurable input filter of 0–30,000 µs, enabling reliable sampling of fast-changing signals. Typical module current draw is around 275 mA at 5.1 V. In Rockwell’s terminology it is a “fast peer control input module,” designed to plug into a ControlLogix backplane and feed discrete status into the controller. Common applications include reading contact closures from sensors, limit switches, and proximity sensors in automated machinery and process lines that require fast, isolated digital inputs and robust operation in challenging environments.