Allen-Bradley 1756-IT6I2 ControlLogix Enhanced Thermocouple Input Module

The Allen-Bradley 1756-IT6I2, also cataloged as the 1756-IT6I2 Analog Thermocouple Module, operates as a dedicated hardware component for isolated temperature signal acquisition within ControlLogix platforms. The module provides six isolated thermocouple and millivolt input channels with dual cold junction compensation sensors and 16-bit signal conversion.

Hardware Specifications

ControlLogix Isolated Thermocouple Signal Processing

The 1756-IT6I2 module performs thermocouple and millivolt signal conversion through six individually isolated input channels. Each channel maintains electrical separation for field signal processing and supports multiple thermocouple types including B, C, D, E, J, K, L, N, R, S, and T.

The module uses 16-bit analog conversion with configurable data representation through integer mode or IEEE 32-bit floating point format. Dual cold junction compensation sensors provide temperature reference measurement for thermocouple calculations.

ControlLogix Backplane Communication and I/O Scaling

The 1756-IT6I2 integrates with the ControlLogix chassis backplane for controller communication and I/O configuration. The module uses backplane bus communication for transferring processed analog values and diagnostic information to the ControlLogix processor.

The isolated six-channel architecture supports I/O density scaling within ControlLogix systems while maintaining separate thermocouple input paths. Firmware configuration compatibility allows channel parameters, filtering settings, and sensor selections to be managed through the ControlLogix programming environment.

Frequently Asked Questions (FAQ)

Q: How many thermocouple input channels are available on the 1756-IT6I2 module?
A: The module provides six individually isolated thermocouple and millivolt input channels with two cold junction compensation sensors.

Q: What backplane current requirements apply to the 1756-IT6I2?
A: The module requires 200 mA at 5 VDC and 120 mA at 24 VDC from the ControlLogix chassis backplane.

Q: Which data formats are supported by the module?
A: The module supports integer mode with left justified 2s complement representation and IEEE 32-bit floating point data format.

Field Installation Guidelines

Install the 1756-IT6I2 module in a compatible ControlLogix chassis slot and verify available backplane power capacity before operation. Use compatible 1756 series removable terminal blocks for field wiring connections.

Route thermocouple cables separately from high-voltage conductors and switching devices to minimize electrical interference. Maintain correct thermocouple extension wire type and polarity during installation.

Connect cable shields according to the site grounding standard. Verify channel configuration, sensor type selection, cold junction compensation settings, and input range parameters before placing the module into service.