Allen-Bradley 1746-NT8 | SLC 500 Thermocouple/mV Analog Input Module

Overview

The 1746-NT8 is an 8-channel SLC 500 analog input module designed for thermocouple and millivolt signals. It supports both fixed and modular SLC 500 installations.

Input Channels and Compatibility

This module accommodates J, K, T, E, S, R, B, and N thermocouples. It also accepts ±50 mV and ±100 mV signals for precise measurement applications.

Memory and Conversion

The 1746-NT8 uses Sigma-delta A/D conversion with 16-bit input and 14-bit output resolution. Step response times are 60 ms in and 2.5 ms out for accurate data acquisition.

Backplane and Power

It draws 120 mA at 5V DC and 70 mA at 24V DC, with total power consumption of 2.28W. The module installs in any SLC 500 chassis slot except Slot 0.

Protection and Isolation

The 1746-NT8 provides input overvoltage protection of ±30 VDC and 600 W pulsed for 1 ms. Isolation tests include 12.5 VDC between inputs, chassis ground, and backplane.

Environmental Specifications

The module operates between 0°C and 60°C and withstands storage from -40°C to 85°C. It functions reliably at 5–95% humidity without condensation.

Additional Features

Included are two cold-junction compensation sensors with ±1.72°C accuracy. The module features nine LED indicators for channel and module status, programmable open-circuit detection, and a low-pass digital filter.

Compliance

The 1746-NT8 is UL and CUL-approved, ensuring adherence to industrial safety and reliability standards.