Allen-Bradley 1746-NI8 Eight Channel Analog Input Module

Allen-Bradley 1746-NI8 Eight Channel Analog Input Module is an eight-channel analog input card for the SLC 500 PLC family, designed to connect sensors and transducers that output voltage or current signals to a backplane-based controller. The module provides eight differential input channels, each of which can be configured per channel to accept voltage or current inputs, enabling flexible integration of process signals onto a single module in a rack. For wiring, use the removable terminal block 1746-RT25G and install conductors up to 14 AWG; Belden 8761 or equivalent is a common reference for recommended wiring. Backplane power is supplied through the chassis with a typical consumption of 200 mA at 5 V and 100 mA at 24 V. Status is indicated via a 9-LED cluster: eight channel indicators plus a module status LED, with open-circuit and out-of-range conditions reported per channel. Addressing on the SLC 500 backplane follows standard module slot conventions, allowing straightforward data readouts by RSLogix 500 programs. The NI8 is used to sample multiple analog signals from sensors such as temperature, pressure, flow, or level transducers and feed that data into the PLC for scaling, monitoring, and control logic. Official documentation and cutsheets describe the eight-channel differential input circuitry and associated wiring options, confirming the NI8 as a high-density analog input option within the SLC 500 line and reflecting its historical place in Allen-Bradley’s SLC product family.