Temperature measuring instruments are critical across many industries and also across a number of commercial applications involving air and gas. Thermocouples and Custom Resistance Temperature Detectors also referred to as RTDs are two widely used devices which help in this operation. Thermocouples have been traditionally used across, but RTDs prove to be better, especially when it gets to providing measurements of high accuracy.
RTDs are made of an element that consists of a coiled wire wrapped around a glass or ceramic core. The material of the wire is usually a pure metal with typical choices being platinum, nickel or copper. The elements, being fragile, need to be protected by a probe and sheath. The change of the resistance of this element with change in temperatures is known, and this correlation can then be used to calculate the temperatures.
RTDs contain sensors that are made up of an element a coiled wire around a core made of glass or ceramic. The material of the wire is pure typically platinum, nickel or copper. RTD elements are however very fragile and can also be very easily contaminated. They are enclosed by a probe or a sheath for protection.
RTDs are also better than thermocouples considering better repeatability. Thermocouples are increasingly being replaced in applications below 600 degrees Celsius. RTD sensors are also available in a variety of form factors and are usually more stable.
However, in case of critical applications involving quick response time, thermocouples are ideal. Thermocouples are also used when the temperatures are not appropriate for RTDs, that is, above 660 degrees Celsius. At these high temperatures, elements of RTDs incline to get contaminated. Also at temperatures below 270 degrees Celsius, the sensitivity of the element drops down to zero. Thermocouples are smaller in size as likened to RTDs and are also used in applications where size can prove to be a concern.
Another classification of RTDs is on the basis of installation, and they may either be immersion sensors or surface mounted sensors. Immersion sensors are mostly used to measure the temperatures of gases and fluids in tans and pipes. Surface mount sensors are in the form of blocks or cylinders and are used whenever immersion is not possible.
RTDs can be installed in either of two ways and as are such classified as either being immersion sensors or surface mounted detectors. Immersion type sensors are used to measure temperatures by immersing the part into fluids and gases in pipelines and tanks. Surface mount sensors can be shaped as cylinders or blocks and are usually used in case immersion is not possible. Manufacturers also provide additional accessories for connection and associated mounting hardware along with RTDs.
Temperature sensing applications are critical in industries and other commercial gas and air applications. Resistance Temperature Detectors RTDs are high precision sensors for these applications. While they do score over thermocouples in terms of higher accuracy, lower drift, and greater stability and are suitable for precision applications, RTDs can easily get contaminated and only work over a specified temperature range. However, with advancements in technology, they are slowly but surely moving towards eliminating thermocouples altogether.
RTDs are made of an element that consists of a coiled wire wrapped around a glass or ceramic core. The material of the wire is usually a pure metal with typical choices being platinum, nickel or copper. The elements, being fragile, need to be protected by a probe and sheath. The change of the resistance of this element with change in temperatures is known, and this correlation can then be used to calculate the temperatures.
RTDs contain sensors that are made up of an element a coiled wire around a core made of glass or ceramic. The material of the wire is pure typically platinum, nickel or copper. RTD elements are however very fragile and can also be very easily contaminated. They are enclosed by a probe or a sheath for protection.
RTDs are also better than thermocouples considering better repeatability. Thermocouples are increasingly being replaced in applications below 600 degrees Celsius. RTD sensors are also available in a variety of form factors and are usually more stable.
However, in case of critical applications involving quick response time, thermocouples are ideal. Thermocouples are also used when the temperatures are not appropriate for RTDs, that is, above 660 degrees Celsius. At these high temperatures, elements of RTDs incline to get contaminated. Also at temperatures below 270 degrees Celsius, the sensitivity of the element drops down to zero. Thermocouples are smaller in size as likened to RTDs and are also used in applications where size can prove to be a concern.
Another classification of RTDs is on the basis of installation, and they may either be immersion sensors or surface mounted sensors. Immersion sensors are mostly used to measure the temperatures of gases and fluids in tans and pipes. Surface mount sensors are in the form of blocks or cylinders and are used whenever immersion is not possible.
RTDs can be installed in either of two ways and as are such classified as either being immersion sensors or surface mounted detectors. Immersion type sensors are used to measure temperatures by immersing the part into fluids and gases in pipelines and tanks. Surface mount sensors can be shaped as cylinders or blocks and are usually used in case immersion is not possible. Manufacturers also provide additional accessories for connection and associated mounting hardware along with RTDs.
Temperature sensing applications are critical in industries and other commercial gas and air applications. Resistance Temperature Detectors RTDs are high precision sensors for these applications. While they do score over thermocouples in terms of higher accuracy, lower drift, and greater stability and are suitable for precision applications, RTDs can easily get contaminated and only work over a specified temperature range. However, with advancements in technology, they are slowly but surely moving towards eliminating thermocouples altogether.
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Read more about Reasons For Using Custom Resistance Temperature Detectors In The Manufacturing Sector.
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