The principal of the Resistance Temperature detector (RTD) is not nearly as complex as that of a thermocouple. Basically, the principal of operation depends on the fact that the electrical resistance of metals varies directly with temperature, and is reproducible to a high degree of accuracy.  The curve of temperature versus resistance for a given wire material can thus be predicted by employing a constant, known as the temperature coefficient of resistance. Useful sensitive elements of RTD’S are those which show a resistance temperature relationship of acceptable magnitude. Two such metals are Platinum and Nickel.

RTD’s are commonly used in sensitive areas requiring much tighter accuracy than thermocouples.

GIC Thermodynamics’ sales and engineering staff will assist you with designing the best RTD sensor style to fit your process and application. Selecting the proper sensor style is very important, as each application or process has its own specific inherit problems that require careful consideration in order to determine the sensors life, accuracy, and dependability. When choosing a sensor it is important to consider its location, temperature range, accuracy required, how rapidly the temperature cycles, heat conduction, process environment, vibration, and ease of installation. If you need additional assistance with the selection of a sensor for your application, please feel free to contact our sales and engineering staff