TMS02

The operating principle of Resistance Temperature Detectors (RTDs) is based on the property that the resistance of metallic conductors varies with temperature. The core principle is as follows: when temperature changes, the amplitude of lattice vibration in metallic conductors such as platinum and copper alters, hindering electron movement to different extents and thereby changing the resistance value. Taking the Pt100 platinum RTD as an example, its nominal resistance is 100 Ω at 0 °C. The resistance increases by approximately 0.385 Ω for each 1 °C rise in temperature, exhibiting highly linear characteristics within a certain temperature range. In practical measurement, a constant‑current source or bridge circuit converts resistance variations into electrical signals. Three‑wire or four‑wire wiring eliminates lead‑wire errors, and resistance values are finally converted into temperature values according to international standard reference tables. Thermocouples feature a simple structure and rugged construction. Thermocouple sensors perform temperature measurement based on the Seebeck effect. Two dissimilar conductors are connected to form a closed loop. A tiny voltage difference is generated in the loop when the two junctions are at different temperatures. This voltage difference is known as thermal voltage or thermoelectromotive force. Its magnitude depends on the materials of the two conductors and the temperature difference between the "measuring junction" (the junction of the two conductors) and the "cold junction" (the open‑circuit ends of the conductors). Therefore, thermocouples are generally used for temperature‑difference measurement. The absolute temperature at the measuring junction can be obtained if the cold‑junction temperature is known, or measured and compensated separately. Standards IEC 60584 and ASTM E230/ANSI MC96.1 list common thermocouple conductor material combinations and their corresponding thermal‑voltage‑to‑temperature characteristics.

High‑end Application

The iTHERM TMS02 MultiSens Flex is designed in accordance with the highest safety standards and allows customization for different applications. Its bendable temperature‑measuring inserts enable 3D temperature measurement via a single process connection. The instrument can be used with or without a thermowell. It features fast response time, high mechanical strength and replaceable sensors. It adopts thermocouple or RTD technology, or iTHERM StrongSens, and is equipped with an advanced diagnostic chamber to provide additional safety protection.