1771-IV8 Ser A (PU)

Allen Bradley Bulletin 1771 | DC True Input Module

Allen Bradley Bulletin 1771 | 8-Point 24VDC Sourcing Input Module, Voltage Range 10-30VDC, Series A

The Allen-Bradley 1771-IV8 is an 8-point discrete DC input module designed for the 1771 Universal I/O platform. Unlike standard sinking modules, the 1771-IV8 is a sourcing input module, meaning it is designed to interface with field devices that sink current It provides a rugged and deterministic interface for PLC-5 controllers to monitor the state of 24VDC sensors, limit switches, and pushbuttons.

This Series A module features 8 independent sourcing input channels operating within a voltage range of 10 to 30VDC (24VDC nominal). To ensure maximum system reliability, the module provides high-grade optical isolation between the field-side wiring and the sensitive backplane logic, preventing electrical noise or transients from affecting the processor. It utilizes the standard 1771-WH field wiring arm, allowing for rapid "plug-and-play" module replacement without the need to disconnect individual field wires.

Performance is optimized for standard industrial control, offering a typical signal delay of 1.0ms for both ON and OFF transitions. This fast response time makes it suitable for high-speed machinery and general automation tasks. The front panel is equipped with 8 dedicated status LEDs that provide clear visual diagnostics, allowing operators to immediately identify the state of each input channel during operation or troubleshooting.

Built for heavy-duty industrial environments, the 1771-IV8 operates reliably between 0–60°C (32–140°F). It features a low power consumption profile, drawing only 150mA at 5VDC from the chassis backplane. The module is designed to withstand significant operational shock and vibration and is UL listed, CSA certified, and CE  compliant, meeting the rigorous standards required for global industrial deployment.

Key Specifications:

  - Inputs: 8 (Sourcing)
  - Nominal Voltage: 24VDC
  - Voltage Range: 10–30VDC
  - Backplane Current: 150mA @ 5VDC
  - Signal Delay: 1ms (typical)
  - Wiring Arm: 1771-WH
  - Platform: 1771 Universal I/O (PLC-5)
  - Series: A