The E.M.F.-Temperature Calibration of Platinum, 10% Rhodium-Platinum and Platinum, 13% Rhodium-Platinum Thermocouples over the Temperature Range 0 -1,760 C

E M.F -temperature reference tables are given for platinum, 10% rhodium-platinum and platinum, 13% rhodium-platinum thermocouples over the range from 0° to 1,760° C. The tables are based on the calibration of twelve thermocouples of each kind, six from each of two manufacturers. Each set of six thermocouples comprised two samples from each of three batches of wire The calibrations are in terms of the International Temperature Scale as revised at the Ninth General Conference of Weights and Measures held in Paris in October 1948 The methods of intercomparison between the thermocouples and the various interpolation instruments specified in the International Temperature Scale are described. It is shown that the difference between the new tables and the old are mainly due to changes in the International Temperature Scale, and that the new tables represent the shape of the E.M.F.-temperature characteristics of the thermocouples of either make sufficiently closely to give interpolation between calibration points with accuracy within ±1° C up to 1,063° C., ±2° C. up to 1,550° C., and ±3° C. above this temperature.