Production temperature-rise tests on transformers

A method is suggested for deducing the ultimate temperature-rise of a transformer from a heat run lasting only 6 hours. It is believed that the deductions from this method are at least as accurate as the conclusions from runs of long duration, which have hitherto been customary. No assumptions are involved as regards the length of time corresponding to the practical meaning of ¿steady, final, ultimate¿ and ¿infinity,¿ or as regards the calculation of the ¿time-constant.¿ Moreover, the method is applicable to interrupted runs. It is hoped that the publication of this paper will prompt the circulation of other suggestions for saving time and electrical energy during the period of the present emergency conditions. In the title of the paper the term ¿production¿ is used in the same sense as in commercial work, in contradistinction to the terms ¿research¿ and ¿development.¿