Comparison of methods for nonlinearity correction of Platinum resistance thermometer

This paper describes the comparison of two methods for nonlinearity correction of Platinum resistance industrial thermometers in production phase. Temperature measurement is done by industrial thermometer based on measuring inlet and is made by Platinum resistance sensor. Measuring range of such thermometers is between -50 °C and +600 °C. As the measuring sensor has not linear transfer function it is necessary to make its correction. It is possible to do this on two ways: by predefined table of values of temperature and related resistance, or by temperature calculation using equations. The comparison of these methods is interesting to know how to choose the better solution and include it in thermometer and computing the microcontroller resources, while keeping the approximation error within the allowed boundaries.