Allen-Bradley 1746-NI4 Input Module

The Allen-Bradley 1746-NI4 is a four‑channel analog input module designed for the SLC 500 family and installed in an SLC 500 chassis to monitor sensors that produce voltage or current signals. Each channel supports voltage or current input with 16‑bit two’s complement resolution and an update time of 512 µs for all channels in parallel, enabling timely monitoring of multiple analog signals. The module provides 500 V DC isolation between field wiring and the backplane, helping protect the controller from transients, and it requires a removable terminal block for field connections. When wiring, Belden 8761 shielded cable is recommended, with a maximum wire size of #14 AWG. Factory calibration simplifies setup and helps ensure measurement accuracy across channels. This device is compatible with Rockwell’s SLC 500 systems, and backplane current is typically 55 mA at 5 V. Note that Rockwell discontinued the 1746-NI4 as of April 29, 2021.