Do you know what thermocouples and thermopiles are? Actually, in the field of temperature measurement, thermocouple and thermopile are two commonly used sensors. But many people are not clear about their differences. Next I will introduce the differences in detail to help you make the right choice according to your needs.

What is a thermocouple?

A thermocouple is a temperature sensor widely used for measurement and control, and also for converting temperature gradients into electrical energy.

 A thermocouple consists of two conductors made of two different materials (usually metal alloys) that produce a voltage near the point of contact between the two conductors. Thermocouples exhibit good performance at low temperatures and are suitable for temperature measurement. When the temperatures at the two ends are different, an electric potential is generated in the circuit, and the temperature is determined by measuring the electric potential.

It is characterized by its simple construction, wide measurement range, and stable performance in extreme temperature environments.

What is a thermopile?

A thermopile is a sensor consisting of multiple thermocouples connected in series. It superimposes the outputs of multiple thermocouples to increase sensitivity and measurement accuracy. Thermopiles are typically used to measure smaller temperature changes or in scenarios where higher accuracy is required.

Comparison of Principles of Operation

 Thermocouple Based on the Seebeck effect, two metals produce a temperature difference electromotive force

Thermopile Multiple Thermopiles Multiple thermocouples connected in series to enhance the electric potential output.

Key Differences 

Measurement Accuracy

Thermocouples typically have an accuracy of ±1°C to ±5°C, whereas thermopiles can have an accuracy of ±0.1°C to ±1°C. Thermopiles reflect temperature changes more accurately due to the stacking of multiple thermocouples.

Measuring Range

Thermocouples have a much wider measuring range and can accommodate both very high and very low temperature environments. Thermopiles have a relatively narrower measurement range.

Response Time

Thermocouples have a faster response time, responding to temperature changes within milliseconds. Thermopiles, due to their more complex construction, typically have response times between tens and hundreds of milliseconds.

Cost

Thermocouples are less expensive and simpler to manufacture. Thermopiles are relatively costly due to the inclusion of multiple thermocouples and complex circuitry.

Application Scenarios

Application of Thermocouples

Industrial Furnace Temperature Measurement.

Automotive Engine Temperature Monitoring.

Temperature Detection in High Temperature Environments.

Application of Thermopiles

 Non-contact temperature measurement .(e.g. infrared thermometer)

Body temperature detection in medical devices.

Measurement of subtle temperature changes in environmental monitoring.

Focusens Solution Advantages

As a technology-based company with 15 years of sensor R&D experience, Focusens can provide:

Customized development service: Adjust the temperature measurement range, response time and other parameters according to customer needs.

Quality calibration service: Strictly in accordance with ISO9001:2015, Focusens can provide a wide range of services to meet customer needs. Controlled in accordance with ISO9001:2015, every part we deliver is tested at least 2*100%.

Service: rapid response within 24 hours throughout the year.

Capability: We develop more than 100 new products every year.

Export: We have exported to more than 60 countries worldwide.

How to choose?

 If you need to measure very high or low temperatures and do not require high accuracy, choose Focusens's line of industrial grade thermocouples. If you need to measure small temperature changes with high accuracy, or for non-contact temperature measurement, we recommend their thermopile sensor modules, some of which also support digital signal output.

Summary

Thermocouples and thermopiles differ significantly in their operating principles, measurement accuracy, range, etc. Focusens, with its professional technical team and rich industry experience, can provide accurate temperature measurement products and solutions according to different application scenarios. If you have more questions about temperature sensors, please contact Focusens technical team for professional advice.