Comparison of platinum resistance thermometers between 63 K and 373.15 K: Part II

Abstract Twelve platinum resistance thermometers were compared with a reference platinum resistance thermometer in the temperature range between 63 K and 273.15 K and at 373.15 K. A constant-temperature bath was used, in which the thermometers were inserted in a copper block immersed in liquid isopentane, propane, oxygen or nitrogen. The differences of the reduced resistances W = R(t) R(0°C) of the thermometers were determined. The results are used to obtain information about the number of calibration points that is required to determine the W vs. T relation of platinum thermometers.