Allen-Bradley 1746-NT8 Thermocouple MV Input Module

The Allen-Bradley 1746-NT8 is an 8-channel, differential thermocouple/millivolt (mV) analog input module designed for the SLC 500 family. It accepts thermocouple signals from common types (J, K, T, E, R, S, B, N) as well as direct millivolt inputs on eight differential channel pairs (CHL 0+ / CHL 0-, through CHL 7+ / CHL 7-), enabling parallel readings from multiple sensors. The module provides cold junction compensation via dedicated CJC inputs (A+/A- and B+/B-), improving accuracy for thermocouple measurements, and it offers up to 500 V DC isolation between each input channel and the chassis ground. Wiring is simplified by a hardware removable terminal block, and status indicators—including a module status LED and per-channel LEDs—facilitate quick fault diagnosis. Typical applications include temperature monitoring and control in process industries, HVAC and furnace monitoring, and lab automation where multiple thermocouple or millivolt measurements must be read by a Rockwell Automation SLC 500 controller. Designed to be installed in a 1746 chassis and used with compatible SLC 500 CPUs, the 1746-NT8 delivers dedicated thermocouple/mV input capability with built‑in CJ compensation for direct temperature-derived signals in PLC programs.