High-temperature measurement system with wireless electronics for harsh environments

High temperature measurement systems do not allow the use of traditional measurement techniques. In the presence of high temperatures the proper functioning of electronics is compromised. Furthermore, if the measurement environment is also hermetic, the traditional cabled measurement technique cannot be adopted. In this article a system to measure the temperature up to 330°C for harsh environments is proposed. The system is based on a hybrid MEMS placed inside the measuring chamber constituted solely by passive components (an inductor connected to a planar micromachined variable capacitor) and an external reading unit, located in the safe environment. The hybrid MEMS was designed and characterized, as well as the electronics of the readout unit. The results obtained and reported in the article are quite good with those measured by a reference instrument. The complete measurement system is presented as a viable solution to the measurement of high temperatures in harsh industrial environments.