Overview
This page is created to help people understand the the most commonly used temperature sensor used in many types thermometers

 

Thermocouples are used in many of our day to day appliances some of which you might not even be ware of.Yet it performs very vital function of measuring temperature in almost all type of environment.(Hot,cold,harsh,smooth,high pressure,low pressure etc). Based on use
they can be divided into industrial and home TC.There working principle is universal but their make and body type are different for different purpose.This is one of the technology which can be accessed by you very easily without the use of any

sophisticated instruments .In fact you can make a thermocouple of your own.See here how

 

 

Introductory questions on thermocouples

What are thermocouples?

Thermocouples are type of temperature sensors.It  produces electrical output relative to the measured temperature.They are most popular type of temperature sensors.They are significant as they have fast reaction time and are portable.They come in varied sizes and are used in various applications.At home they are used in devices like ovens,heaters,refrigerators etc.

In industries they come in the form of probes to insert in the temperature measurement region.They re used in power plants and any other industrial machines or region where monitoring the temperature is necessary for safety or controlling purposes.

How were they discovered and what is their principle of operation .

Its principle is based on the seebeck effect which was discovered by T.J seeback in 1831.He discovered that when two metals of different wires are joint together and if temperature of the junctions are  different then a current flows through the wires..He also discovered that the Potential  difference generated was almost directly proportional to the difference in the two temperatures for particular range depending on the type of material of which it is made.

Why they are called so?

Thermo-couples are formed by joining together two different metals to form couples and its working is based on the thermo electric effect   which by definition is generation of electrical output when subjected to temperature  or thermal energy.

Thermocouple theory

What is temperature

What causes Seebeck effect

Thermocouple working principle

Laws of thermocouples

Types of thermocouples

Junction types and errors in thermocouples

Drift and decalibration

Accessories (transmitters,plugs extension wires etc)

Household application