46 THE DESIGN OF STATIC TRANSFORMERS 



the core. In order, therefore, to obtain the required section 

 of iron, the gross cross-section of the core must he 



63,6 



0,90 



= 70,0 sq cm. 



Cruciform <Steftped Cruc/form 



FIGS. 22 to 25. Types of sections of transformer cores. 



The preferable shape of the cross- section is in itself a ques- 

 tion requiring careful study. Some of the various types which 



FIG. 26. Core section for elliptical-shaped coil. 



have been used, and some of which are still in common use, 

 are indicated in Figs. 20 to 26. Figs. 20 and 21 show the 

 square- and oblong-sectioned cores with similarly-shaped coils 



