Linear sensors – also called RTD (Resistance Temperature Detectors) are generally made by pure metal or by a metal alloy whose variation of resistance is placed, in the industrial field, in the linear zone. As a result, the conversion between resistance and temperature can be reduced in the first approximation to a coefficient.
The most common linear sensor in industrial field are platinum-based ones, such as PT 100 and PT 1000.
Generally, linear temperature sensors (PT 100 – PT 1000) are used in industries which requires the calculation of temperature’s absolute values, with extreme precision and repeatability, where the measuring range is wide. Typical examples are electromechanical industry, chemistry industry, medical industry, aeronautical industry etc.