# Thermocouple Vs Thermopile sensor | Difference between Thermocouple and Thermopile sensor

This page compares Thermocouple vs Thermopile sensor and mentions difference between Thermocouple and Thermopile sensor.

## Thermocouple and its types

The electrical device made of two dissimilar conductors forming electrical junctions at different temperatures is known as thermocouple. It produces voltage which is dependent on temperature. Due to this thermoelectric effect, it is known as thermoelectric transducer.
Refer difference between thermocouple types>> which include type-J, type-K, type-T, type-N, type-E, type-B, type-R and type-S. and also difference between Thermocouple vs RTD vs Thermistor>> including their functions, advantages and disadvantages in order to compare them.

## Thermopile sensor

Thermopile is composed of pair of thermocouples or more arranged in series or parallel. It produces higher voltage output compare to single thermocouple. Moreover unlike thermocouple which is contact based temperature sensor, thermopile is non contact based temperature sensor device. It uses infrared radiation for temperature measurement along with IR Absorber device.
Refer Thermopile sensor basics and its working operation>>.

Following table mentions comparison between thermocouple and thermopile sensor types.

Features Thermocouple Thermopile
Size It is thinner and has pointed end It is bigger and thicker
Voltage output Lower, between 8 mV to 30 mV Higher, in 10s or 100s of mVs
Structure Two dissimilar conductors i.e. made of single pair of wires More than one thermocouples arranged in series/parallel along with IR absorber membrane
Mathematical Equation Vout = S*(Tx-TREF) Vout = N*S*(Tx-TREF)
Where, N is number of thermocouples used in a thermopile
Application It is used for contact based temperature measurement It is used for non-contact based temperature measurement due to use of IR (infrared radiation) mechanism employed.