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Pyrometer- Working Principles and Their Types

Thermometers are incredibly useful, but what happens when the temperatures get too high to use them, like in a furnace? Enter pyrometers, which are instruments developed to measure higher temperatures without contact by using optical devices. By measuring an object’s electromagnetic radiation, pyrometers can determine its temperature. Specifically, pyrometers are devices which measure the thermal and infrared radiation that is emitting from an object in order to determine its temperature without direct contact. When temperatures of an object exceed 65 degrees Celsuis, touching it would melt a thermocouple, thermistor, or thermometer. Other situations in which you might need to use a pyrometer include other instances where touching the object would damage the temperature measurement device, when the object is incredibly hazardous, or when the object is in motion and is difficult to pin down for a temperature reading. A hot object will release thermal energy through electromagnetic radiation, and measuring that radiation helps a pyrometer determine its temperature.

There are two general kinds of pyrometers: optical and infrared, or radiation, pyrometers. First, radiation pyrometers are built on the principle that everything will emit radiation at very high temperatures. This causes the object to appear incredibly bright, and it will change colors because of the alteration in wavelength. While facing the source of heat, the radiation reflects at an angle and becomes focused at the pyrometer’s thermocouple, which produces an electric current based on the heat it gives off. This current turns a dial which shows the current temperature of the object at that moment. They’re built from pyroelectric materials including lithium tantalate and triglycine sulfate.

An additional pyrometer type is the optical pyrometer, which is built to determine the level of thermal radiation that is present in the visible spectrum. In order to measure the temperature of very hot objects, optical pyrometers track the color of light they give off. They are able to compare the light source and the surface in question; when the object and the filament’s temperatures match, their thermal radiation intensity will match up as well. This means that the filament will become nearly invisible. As the current passes through the filament, it can be converted into a temperature that can be read.

The infrared thermometer is an example of a modern day pyrometer. Any item possessing a temperature greater than absolute zero gives off infrared radiation. When the surface temperature is higher, the radiation’s frequency will increase as well. Specifically with infrared thermometers, they are able to determine the infrared radiation frequency, which is converted into a value for the temperature. In order to discover how these pyrometers work, it’s important to know they can be broken up into two general parts: the optical system and the detector. The optical system of the pyrometer features a lens which focuses the object’s released radiation onto the detector, which is able to register the focused radiation and convert it into a temperature measurement.

When something is too hot or dangerous to directly contact in order to obtain a temperature reading, pyrometers become crucial. By measuring the radiation emitting from the object in question, a pyrometer is then able to convert this energy into a temperature reading using a lens that reflects an object’s radiation onto a temperature detector. Whether you’re searching for high quality pyrometers or reliable IT hardware components, Internet of Hardware has the parts you need. Peruse through more than two billion parts available in our catalog; you can rest assured knowing that many parts are subject to rigorous quality assurance measures. Once you place an order with us, we work diligently to get the products you need delivered to you as quickly as possible. Our commitment to fast turnaround times keeps our clientele returning when in need of additional parts. You can trust Internet of Hardware for all your hardware component needs.


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