Allen-Bradley 1794-IT8 | FLEX I/O 8-Channel Thermocouple Input Module

Product Overview

The 1794-IT8 is a high-resolution thermocouple and millivolt input module designed for the Allen-Bradley FLEX I/O platform. It features eight independently configurable differential input channels, capable of supporting a diverse array of thermocouple types (B, C, E, J, K, N, R, S, T) as well as direct low-level millivolt signals. By utilizing a 16-bit Sigma-Delta analog-to-digital converter, the 1794-IT8 ensures exceptional precision for critical thermal monitoring applications in industrial environments. Its modular design allows for distributed placement close to field sensors, effectively minimizing long runs of expensive thermocouple extension wire and reducing potential signal interference.

Technical Specifications

The 1794-IT8 offers a professional-grade feature set for precision temperature acquisition:

• Manufacturer: Rockwell Automation / Allen-Bradley

• Model Designation: 1794-IT8

• Input Type: 8 Differential channels (Thermocouple or Millivolt)

• Nominal Input Range: -76.5 mV to +76.5 mV

• Resolution: 16-bit (2.384 μV/LSB)

• Data Formats: 16-bit 2’s complement or Offset Binary

• Input Impedance: > 10 MΩ

• Isolation Voltage: 850 V DC (Inputs to logic, tested for 1 s)

• Flexbus Current: 20 mA @ 5 V DC

• Power Dissipation: Max 3.0 W @ 31.2 V DC

• Cold Junction Compensation: External CJC sensors required on terminal base

• Compatible Terminal Bases: 1794-TB2, 1794-TB3, 1794-TB3T (Recommended for CJC)

• Status Indicators: 1 Red/Green LED for module health and power status

• Dimensions (H x W x D): 94.0 x 45.7 x 53.3 mm (3.7 x 1.8 x 2.1 in)