Allen-Bradley 1756-IB32 32-Point Digital Input Module

The Allen-Bradley 1756-IB32 is a 32-point digital input module for ControlLogix systems that accepts 10–31.2 V DC inputs and presents sinking, 24 VDC signals to the 1756 backplane, organized as two 16-point groups on a 36-pin interface and wired through removable terminal blocks such as 1756-TBCH or 1756-TBS6H; it is designed for backplane mounting in a ControlLogix CPU rack and requires a compatible 1756 chassis. The module’s inputs are a 24 V DC nominal type with an on-state current of 4.8–5.5 mA (10–31.2 V), off-state current up to 2.27 mA, and an off-state voltage maximum of 5 V, with input delay times specified as 380 µs max from Off to On plus a user-selectable filter of 0, 1, or 2 ms, and 420 µs max from On to Off plus a filter of 0, 1, 2, 9, or 18 ms; the backplane power draw and dissipation are 120 mA at 5.1 V and 2 mA at 24 V, with a total backplane power of about 0.66 W and maximum module power dissipation of 6.2 W at 60 °C (140 °F), equating to a thermal dissipation of 21.1 BTU/hr at that temperature. With 32 discrete inputs, the IB32 is ideal for reading switches and 24 V sensors in industrial automation, manufacturing lines, and other ControlLogix-based control applications requiring a dense, reliable 24 VDC input interface.