Introduction to the 1756-IT16 Non-Isolated Thermocouple/mV Input Module

When precise temperature monitoring is critical in advanced control applications, the 1756-IT16 from Allen-Bradley / Rockwell Automation provides a reliable solution. This enhanced I/O module is part of the ControlLogix 1756 family and is designed for high-density temperature sensing. With 16 non-isolated channels, it supports B, C, E, J, K, N, R, S, T, and mV type sensors. The module offers 24-bit data resolution and cold junction temperature compensation for accurate readings.

Key Features & Technical Specs of the 1756-IT16

• Brand: Allen-Bradley / Rockwell Automation, Series: ControlLogix
• Part Number: 1756-IT16, Module type: Analog input, thermocouple mode
• Number of channels: 16, non-isolated, with 24-bit data resolution
• Input/output range: -100 to 100 milli Volts, max. 5 Volt-Amps
• Isolation voltage: 250 Volts (continuous)
• Current draw: 200 milli Amps at 5.1 Volts DC, 80 milli Amps at 24 Volts DC
• Operating temperature: 0 to 60 degrees Celsius (32 to 140 degrees Fahrenheit)
• Enclosure type: None (Open-style), Mounting: Chassis, Display: Status LED

Unique Insight: The 1756-IT16 requires two CJC sensors (product code 1756-CJC, sold separately) for thermocouple mode operation. This ensures accurate cold junction compensation, which is vital for precise temperature readings in demanding environments.

Applications & Use Cases

In industrial settings, the 1756-IT16 excels at monitoring temperature in processes such as chemical reactors, furnaces, and heat exchangers. For instance, in a petrochemical plant, it can track multiple thermocouple points simultaneously, enabling operators to detect temperature deviations early. This module also supports mV input, making it suitable for strain gauge or pressure transducer applications. Its high-density 16-point design reduces the number of modules needed, saving rack space and simplifying wiring.

Installation & Setup Guide

Mount the 1756-IT16 directly into a ControlLogix chassis. Ensure the module is properly seated and secured. Connect thermocouple or mV sensors to the terminal block, observing polarity. For thermocouple operation, install two CJC sensors (1756-CJC) as per the manual. The status LED provides visual indication of module health. Always follow Allen-Bradley installation guidelines to avoid wiring errors.

Maintenance & Reliability Tips

Regularly inspect the 1756-IT16 for dust or debris buildup on the open-style enclosure. Verify that all connections remain tight and that the CJC sensors are functioning correctly. Check the operating temperature range (0 to 60 degrees Celsius) to ensure the module is not exposed to extreme conditions. Periodic inspection per the manufacturer's manual helps maintain long-term reliability and reduces unexpected downtime.

Compatibility & Integration

The 1756-IT16 integrates seamlessly with ControlLogix controllers and the 1756 chassis. It works with a wide range of thermocouple types (B, C, E, J, K, N, R, S, T) and mV sensors. For system expansion, pair it with other ControlLogix analog or digital modules. Refer to the Allen-Bradley documentation for specific controller compatibility and configuration steps.

Comparison with Similar Modules

Compared to isolated thermocouple modules, the 1756-IT16 offers a non-isolated design that reduces cost and complexity while maintaining high channel density. Unlike general-purpose analog input modules, it provides dedicated thermocouple linearization (ITS-90) and cold junction compensation. For applications requiring isolation, consider isolated variants; for high-density, non-isolated temperature sensing, the 1756-IT16 is an optimal choice.

FAQ about the 1756-IT16

Q: What is the input range of the 1756-IT16?

A: The input/output range is -100 to 100 milli Volts, with a maximum of 5 Volt-Amps.

Q: How many channels does the 1756-IT16 have?

A: It has 16 non-isolated channels.

Q: What is the data resolution of this module?

A: The data resolution is 24-bit.

Q: Does the 1756-IT16 require CJC sensors?

A: Yes, it requires two CJC sensors (1756-CJC, sold separately) for thermocouple mode operation.

Q: What is the operating temperature range?

A: The operating temperature is 0 to 60 degrees Celsius (32 to 140 degrees Fahrenheit).

Q: What is the current draw at 5.1 Volts DC?

A: The current draw is 200 milli Amps at 5.1 Volts DC and 80 milli Amps at 24 Volts DC.

Product Support & Availability

The 1756-IT16 is available from PetroPartsOnline. In stock and ready to ship, this module is a reliable choice for your ControlLogix system. Contact PetroPartsOnline for current lifecycle status and ordering details.