Thermocouple Measurement


Thermocouple Measurement

NAI's latest generation Thermocouple Module (TC1) is used on our rugged COTS Multifunction Embedded I/O Boards, Single Board Computers (SBCs), and Configurable Systems offered in OpenVPX, cPCI, VME, and PCI/PCIe configurations.

This module provides up to eight individual isolated thermocouple or low-voltage range measurement channels. Full featured programmability provides interfaces for virtually all industry standard NIST temperature ranges (J, K, T, E, N, B, R, and S thermocouple types).

NAI's Smart Function Modules provide uniquely flexible, mix & match customization options for use with our COTS hardware. Learn More

Module TC1

A thermocouple is a temperature-measuring device typically consisting of two dissimilar conductors that contact each other at one or more spots. It produces a voltage when the temperature of one of the spots differs from the reference temperature on other parts of the circuit. Thermocouple temperature sensors are widely used for measurement and control, and can also convert a temperature gradient into electricity.

In contrast to most other methods of temperature measurement, thermocouple modules are self-powered and require no external form of excitation. The biggest limitation with the thermocouple is accuracy; system errors of less than 1° C can be difficult to achieve. Thermocouples are suitable for measuring over a large temperature range, up to 2300° C. Applications include temperature measurement for rocket and/or jet engines, gas turbine exhaust, diesel engines, and other MIL/AERO/INDUSTRIAL embedded or test processes. They are arguably less suitable for applications where smaller temperature differences need to be measured with high accuracy (i.e., the range 0 – 100° C with 0.1° C accuracy). For such applications resistance temperature detectors may be more suitable.

TC1 block diagram

External Thermo-block Interface

Equipped with an externally mounted (2” x 2”) iso-thermal interface/therminal block (optional accessory) for housing a cold-junction-compensation temperature sensor, the TC1 has a direct interface and automatically provides compensated measurements at accuracies up to ±0.2° C. As an option for certain rugged embedded systems and applications, the junction temperature offsets may be directly programmed for standalone operation or via ambient/junction temperature measurement by other means including internal temperature sensor.

The fundamental design is based on independent 24-bit Sigma-Delta A/D converters for each channel; therefore, the TC1 can be alternatively programmed and used for direct precision, low voltage measurements (±100 mV) in other low-voltage range A/D applications (i.e., shunt resistor voltage/current sense measurements).

The TC1 is designed for rugged, embedded “on-the-move” or laboratory-grade environments, and provides continuous Background Built-in-Test (BIT) capabilities for accuracy and “open” detection monitoring and flagging.


Click below for manuals and specifications:

TC18-CH Thermocouple, LV A/DN/AModule Manual - TC1

Function module(s) featured in products below:

ModelBoard TypeBoard ArchitectureFunction Module SlotsSizeEthernetMaster / SlaveOn Board ReferenceOther
75G53U cPCIARM / Xilinx® Zynq3 2 x GbBoth   
64G5VMEARM / Xilinx® Zynq6 2 x GbBoth YUser application ARM processor capability
68G53U OpenVPXDual Core ARM® Cortex® A9 @ 800 MHz3 2 x GbBoth  Slot profile: SLT3-PER-1U-14.3.3 / Module profile: MOD3-PER-1U-16.3.3-2
79G5PCIe 31/2   N/A 
ModelBoard TypeProcessorFunction Module SlotsMaximum MemoryMaximum StorageVideo OptionsEthernetAvailable O/S
75ARM13U cPCI SBCXilinx® Zynq 7015 with Dual Core ARM® Cortex® A9 @ 800 MHz3512 MB DDR3L SDRAM32 GB SATAII NAND FlashN/A2 x GbWind River® VxWorks®, Xilinx® PetaLinux OS and DDC-I Deos™ support
68ARM13U OpenVPX SBCXlilinx® Zynq 7015 & 7016 w/Dual Core ARM® Cortex®-A9 @800MHz3512 MB DDR3 SDRAM32 GB SATAII NAND FlashN/A2 x GbWind River®, VxWorks® and Xilinx® PetaLinux OS Support
75PPC13U cPCI SBCNXP® QorIQ® P2041 Quad-Core e500mc Processor @ 1.2 GHz28 GB DDR3L SDRAM32 GB SATAII NAND FlashN/A2 x GbWind River® VxWorks®
75INT23U cPCI SBCDual Core Intel® i7 3517UE @ 1.5 GHz28 GB DDR3L SDRAM32 GB SATAII NAND FlashVGA, HDMI, LVDS, or DVI2 x GbCentOS, Red Hat®, Linux®, and Windows® Embedded Standard 7
64ARM16U VME SBCXilinx® Zynq Dual Core ARM® Cortex® A9 @ 800 MHz6 + AC Ref512 MB DDR3L SDRAM32 GB SATAII NAND FlashN/A2 x GbWind River® VxWorks® and Xilinx® PetaLinux OS support
68PPC23U OpenVPX SBCNXP® QorIQ® T2080 Quad Core @1.5 GHz2 8 GB DDR3 SDRAM32 GB SATAII NAND FlashN/A2 x GbWind River® VxWorks®
ModelPhotoBoard TypeDimensions w/Connectors (w x h x d)Volume w/Connectors (in3)Weight / lbs (fully populated)Est. Typ. Power Dissipation (W)# of Board SlotsFunction Module SlotsMax I/O PinsEthernet
NIU1AModule6.8" x 1.5" x 2.5"28.90<1.25 to 15 WN/A1592 x Gb
NIU2AModule7.0" x 3.0" x 2.5"52.5<2.755 to 25 WN/A21322 x Gb
SIU313U4.71" x 2.35" x 8.71"96.41<5.07 to 35 W131322 x Gb
SIU333U4.71" x 4.78" x 8.71"196.10<10.014 to 75 W393222 x Gb
SIU353U7.13" x 4.78" x 8.71"296.85<15.025 to 100 W5155122 x Gb