Allen-Bradley 1771-NIV 8-Point Analog Input Module

The Allen-Bradley 1771-NIV 8-Point Analog Input Module (Frn A) is an eight-channel, isolated analog input interface for PLC-5 remote I/O that converts sensor signals into digital data for the controller. Each channel accepts either voltage or current signals, with voltage ranges up to ±5.5 V and current ranges up to ±21 mA, all captured with 16‑bit resolution. Per-channel conversion yields 168 µV/bit for voltage and 330 nA/bit for current in unipolar operation, while input impedance exceeds 10 MΩ for voltage and is about 300 Ω for current. Update time per module can reach up to 25 ms, and the backplane draw is 1.5 A at 5 V. For field wiring, the module supports Remote Terminal Panels (RTPs): 1771-RTP3 for current input and 1771-RTP4 for voltage input. Data is available in BDC or Natural Binary formats depending on configuration, aligning with the legacy PLC-5 architecture. This module is designed for eight independent channels and integrates into 1771 N-series I/O racks, enabling straightforward retrofits or expansions in appropriate PLC environments. Ideal uses include reading sensor voltages from process transducers or converting 4–20 mA loop signals for the PLC, delivering high-resolution, isolated measurement suitable for industrial automation applications.