Allen-Bradley 1771-IBD Input Module

Allen-Bradley 1771-IBD is a 16-point DC input module for the PLC-5 1771 I/O chassis. It accepts 10–30 V DC signals and converts them to logic-level inputs for the controller, with an input impedance up to 2.5 kΩ per channel, a minimum on-state voltage of 10 V DC, and per-channel minimum input currents of 4 mA at 10 V (12 mA at 30 V). The module specifies a maximum off-state current of 2.4 mA and a maximum off-state voltage of 6 V DC, and it draws about 130 mA from the backplane. A fault-mode jumper on the top edge configures Last State Fault Mode, ensuring defined input states if a fault is detected. This Series B compatible 16-point digital input module is used to monitor digital sensors and switches in PLC-5 installations, wiring to AB 1771 I/O backplanes with standard addressing. Typical applications include factory automation, machine control, and batch processes where robust DC input interfacing is required.