Precision Thermocouple Based Temperature Measurement System

Introduction

The objective of this project is to design, build, and validate a precision thermocouple-based temperature measurement system using the Seebeck effect. The system converts the extremely small thermoelectric voltage generated by a thermocouple into accurate, real-time temperature data. Unlike thermistors or integrated circuit temperature sensors, thermocouples are capable of:

• Operating over a very wide temperature range
• Withstanding harsh and high-temperature environments
• Responding rapidly due to low thermal mass

However, the output signal from a thermocouple lies in the microvolt range, making accurate measurement challenging. This project addresses that challenge by implementing:

• A low-noise instrumentation amplifier
• Cold junction compensation (CJC)
• Microcontroller-based digitization, linearization, and calibration