Resistance Temperature Detector Calculator (RTD)

The Resistance Temperature Detector (RTD) Calculator component generates a polynomial approximation for calculating the RTD Temperature in terms of RTD resistance for a PT100, PT500 or PT1000 RTD. Calculation error budget is user-selectable, and determines the order of the polynomial that will be used for the calculation (from 1 to 5). A lower calculation error budget will result in a more computation intensive calculation. For example, a fifth order polynomial will give a more accurate temperature calculation than lower order polynomials, but will take more time for execution. After maximum and minimum temperatures and error budget are selected, the component generates the maximum temperature error, and an error vs. temperature graph for all temperatures in the range, along with an estimate of the number of CPU cycles necessary for calculation using the selected polynomial. Selecting the lowest error budget will choose the highest degree polynomial. For the whole RTD temperature range, -200 °C to 850 °C, the component can provide a maximum error of <0.01 °C using a fifth order polynomial.