What is RTD?
Resistance Temperature Detectors(RTDs) are temperature sensors that contain a resisor that changes resistance value as its temperature changes. they have been used for many years to measure temperature in laboratory and industrial processes,and have developed a reputation for accuracy, repeatability and stability.
Why use an RTD in stead of a thermocouple or thermistor sensor?
Each type of temperature sensor has a particular set of conditions for which it is best suited. RTDs offer several advantages:
1, A wide temperature range(-50~500°C for thin-film and -200 to 850°C, RTDs can be used in all but the highest-temperature in dustrial processes. When made using metals such as platinum, they are very stable and are not affected by corrosion or oxidation.
Other materials such as nickel, copper, and nickel-iron alloy have also been used for RTDs. However, these materials are not commonly used since they have lower temperature capabilities and are not as stable for repeatable as platinum.