INRiM Technical Report 19/2020: "Electromagnetic noise investigation in a commercial furnace for ITS-90 fixed points realization in contact thermometry"

Accurate resistance measurements are essential in a primary temperature laboratory where the International Temperature Scale of 1990 (ITS-90) is realized. Among different noise sources, electromagnetic interference due to furnace heating elements has to be considered and avoided. In this technical report is illustrated the project of a new apparatus for the realization of freezing points from zinc to silver. Commercial available solutions were considered but no information was obtained by manufacturers about the presence of electromagnetic induced noise. Consequently, an experimental test was arranged inside an already available, commercial furnace Carbolite Gero model GHA 12/450 to verify the absence of noise onto resistance measurements during an accurate realization of the aluminum fixed point (660°C). Here, we report the results obtained by the collaboration between the INRiM medium temperature research group and the radiation thermometry group