Hi - I'm a research engineer working in the field of precision measurement for SMS Ltd. Currently looking to measure temperature to extreme accuracy, cheaply! Ultimately a PT100 will be included in a new product, but until then we will probably use a Pico 104 temperature logger for R&D.
My technical question concerns the classification of PT100 sensors. What physically differentiates (say) a Class A from a Class B? Is it merely calibration, or are there internal material/physical differences?