Allen-Bradley 1756-IA16 16-Point 120V AC Digital Input Module

The Allen‑Bradley 1756-IA16 is a ControlLogix 16-point digital input module that provides sixteen discrete 120 VAC inputs for field devices in a ControlLogix system. Operating from 74–132 VAC at 47–63 Hz, each input is conditioned through internal rectification to feed the logic side, and the module uses a 20-pin removable terminal block arranged as two 8-point groups. Power and timing characteristics include a backplane current/consumption profile of about 0.58 W total backplane power, with typical draws of 100 mA at 5.1 V and 2 mA at 24 V, and a maximum dissipation of 5.8 W at 60 °C (18.41 BTU/hr). Electrical specs show an off-state voltage up to 20 V and off-state current up to 2.5 mA; on-state current ranges from 5 mA minimum at 74 V AC to 13 mA maximum at 132 V AC, with inrush up to 250 mA peak decaying to <37% in 22 ms without activation. Timing features include an off-to-on hardware delay of up to 10 ms plus a user-selectable input filter of 1 ms or 2 ms, and an on-to-off delay of up to 8 ms with a 9 ms or 18 ms filter. Firmware support includes v3.004 family compatibility. Typical applications involve interfacing 120 VAC field signals—such as switches, relays, and sensors—into ControlLogix controllers for general-purpose automation, machine control, and process monitoring. The module is compatible with the ControlLogix 1756 backplane and uses a removable, 20-pin terminal block to connect the 16 inputs.