Saturday, 16 April 2016

Temperature measurement techniques

Temperature measurement is another important variable in any process industry. There have been several measuring techniques implemented in order to accurately measure this variable. These different techniques makes use of a variety of devices for measuring temperature. One of the most devices used from centuries till this day have been associated with fluids (like mercury or alcohol). The sole property of fluids to expand during high temperatures and vice versa, is the main reason for this association. However, there are some other instruments/devices which came to used at a later stage; namely, thermocouples, thermostats and resistive temperature devices (RTD) etc.


Resistive temperature detector (RTD)

As the name suggests resistive temperature detector, simply means a device which is used to detect temperature by detecting resistance.

Thermocouple operation

Thermocouple is an instrument used for measuring temperature in the form of voltage. It consists of two pieces of dissimilar metals with their ends joined together by methods such as twisting, soldering or welding.