Temperature sensors are devices used by industry to gather data related to the temperature of liquids. These sensors are found in different varieties and can be used for simple home use to scientific purposes. There are three main types of temperature sensor. These are:
Resistance thermometer detectors
RTD sensors are often made up of metals viz, nickel, copper and platinum. Different metals are used to measure different temperatures. For instance, lower temperatures are measured by copper and nickel RTD sensors.
A sensing element of non-conducting element like glass, ceramic or mica is connected to RTD. Resistance is measured by these elements and the reading is gained.
Thermocouples
Unlike RTD sensors, thermocouples use two different metals to read the temperature. These metals are joined at one end to produce a voltage. This voltage is then converted into a temperature reading. The sensing junction, where the metals meet, is connected to the extension wires making its physical range larger.
Thermocouples are not restricted to any particular metals. Any two metals can be combined as sensing junctions.
Non contact infrared thermometers
Non contact infrared thermometers use non contact methods to work. These thermometers are often used for specific applications that require remote temperature measurement. Infrared thermometers use infrared light instead of metals to read the temperature. A lens is used to focus on the source of which the measurement has to be taken. As no contacts are required for the working of these thermometers, they are used while calibrating thermostats and inbuilt thermometers.
