TIIK IIKATINC OF TKANSFOHM KKS 



143 



the greater the difference between the temperature rise 

 obtained after a few hours run and the stationary value. The 

 etirves A y B, C and D of Fig. 76 (p. 119) refer to the terapera- 

 tuivs <jiven by thermometers placed in the positions shown in 



77 (p. 120). 



The effect of varying the depth of oil in a transformer placed 

 in a 'jivt -n case is illustrated by the data given in Table 15. 

 These data refer to a 100-kva 5000 to 2000-volt 60-cycle 

 le-phase transform*-!-. The first heating test was made 

 with a depth of oil of only 7 cm above the transformer core. 

 I In' figures show that not only is the temperature of the trans- 

 former considerably decreased by the extra depth of oil, but 

 that the distribution of temperature is much more even 

 thn >uv;h nit the whole volume of the oil, thus showing a better 

 circulation. 



TAHLK l'>. HI.AIIV TESTS ox A 100-KVA Ti: \x-i OKMKK. 



III r..nMdrrili'_' tlir Sn|||r\\ ll.il lli^'ll Spent!. ' t . 1 1 1 1 H '1'a t 11 IT |'i>i S 



recorded in tln-x- tr>N, tin- 1- c \\liidi the tests 



namely, twentr-foUF li..iirs at Cull luad, must be 

 kept in mind. 



