Allen Bradley | 1756-IT6I 6-Channel Isolated Thermocouple Input Module

Product Description

The 1756-IT6I module from Allen Bradley’s ControlLogix series is a six-channel isolated analog input device designed for thermocouple measurement. Each input channel is electrically isolated, ensuring accurate signal acquisition and noise immunity in industrial automation environments. With support for multiple thermocouple types, high-resolution conversion, and configurable scan times, it is ideal for advanced temperature monitoring and process control applications.

Technical Specifications

• Manufacturer: Allen Bradley

• Product Line: ControlLogix

• Part Number: 1756-IT6I

• Category: PLC Analog Input Module

• Module Type: Isolated Thermocouple Input

• Number of Inputs: 6 isolated thermocouple channels + 1 CJC (cold junction compensation)

• Supported Thermocouple Types: B, C, E, J, K, N, R, S, T

• Input Resolution: 16-bit

• –12…78 mV: 1.4 µV/bit (typical)

• –12…30 mV: 0.7 µV/bit (high-resolution range)

• Module Scan Time:

• 25 ms minimum (floating point, millivolt)

• 50 ms minimum (floating point, temperature)

• 10 ms minimum (integer, millivolt)

• Data Format: Integer (left-justified, 2’s complement) or IEEE 32-bit floating point

• Backplane Current Draw:

• 250 mA @ 5 VDC

• 125 mA @ 24 VDC

• 2 mA @ 24 VDC (auxiliary)

• Power Dissipation (Max): 4.3 W @ 60 °C (140 °F)

• Isolation Voltage: 50 V continuous

• Removable Terminal Blocks: 1756-TBNH, 1756-TBSH

• Weight: 1.38 lbs (0.62 kg)

• Enclosure Type: Open-style

Key Features

• Six isolated thermocouple inputs with cold junction compensation.

• High-resolution measurement for precise temperature monitoring.

• Configurable scan times for flexible performance.

• Supports a wide range of thermocouple types.

• Compact single-slot design for ControlLogix chassis.

Application Scenarios

• Process industries requiring accurate thermocouple-based temperature monitoring.

• Advanced automation systems with multiple sensor inputs.

• Distributed control systems needing isolated analog input modules.

FAQ

Q: What types of thermocouples are supported by the 1756-IT6I?   A: It supports B, C, E, J, K, N, R, S, and T thermocouple types.

Q: What is the resolution of the module?  A: Resolution ranges from 0.7 µV/bit in high-resolution mode to 1.4 µV/bit in standard ranges.

Q: How does this compare to the 1756-IR6I module?  A: The 1756-IT6I is designed for thermocouple inputs, while the 1756-IR6I is intended for RTD inputs.