The Allen-Bradley 1771-IV is a PLC 5 Digital DC Input Module. It converts DC signals provided by user devices to the logic level needed by the processor. It directly controls the state of corresponding bits in the PLC data table. It provides a modular design with space-saving and pocket-friendly means to add input to a PLC control system. It has a 1771-WA wiring arm for replacing modules, eliminating the need to disconnect any wiring. The 1771-IV is a series A module and supports ?, 1, and 2-slot I/O addressing. It has applications in Sink DC input signal termination. The 1771-IV module has 8 inputs with a 10 – 60V DC Source (Sink load) voltage category. It has an operating voltage range of 12 - 24V DC. Its typical signal delay is 15ms (±7) at On-DC state and 15ms (±7) at Off-DC state. Its maximum Off-state current of 3mA and a backplane current load of 74mA. Its maximum power dissipation is 5.8W and its thermal dissipation is 19.9 BTU/hr. The 1771-IV is installed in a 1771 I/O chassis containing a PLC processor. Keying bands for putting it in the right slot is between pins 8 and 10 for the lower connector and pins 12 and 14 for the upper connector. The 1771-IV module has 8 red status indicators for field side indication at the front panel. It contains optoelectrical isolation to protect the system circuits from electrical transients. It also has input filtering to reduce electrical noise.
ManufacturerRockwell Automation
BrandAllen-Bradley
Part Number/Catalog No.1771-IV
Module TypeDigital DC Input Module
Number of Inputs8 Inputs
Voltage Category10-60 Volts DC, Source (Sink Load)
DC Operating Voltage12-24 Volts
Backplane Current74 Miliamperes
Max DC Off-State Current3.0 Miliamperes
Typical DC Signal Delay (On)15 (+/- 7) ms
Typical DC Signal Delay (Off)50 ms
Wiring Arm1771-WH
Model StatusEarlier Model
Typical AC Signal Delay (Off)45 (+/- 15) ms
MountingRack Mountable