ALTERNATING-CURRENT WINDING 



193 



the latter requires three kinds. This is important if the coils are 

 form-wound, as only two forms will be necessary for the two- 

 range, against three for the three-range. It is, however, true 

 that a two-range winding with a bent coil will require three forms, 

 one for each range, and one for the bent coil, so that such a 

 winding possesses no advantage over a three-range winding so far 

 as the number of forms is concerned. If the windings are carried 

 out by hand, the bent coil can be quite easily carried out by aid of 

 a suitable winding- block (see p. 310, Chap. XII). The two-range 



FIG. 232. Four-pole, Two-phase, Short-coil Winding. 



winding has also the advantage that the ends of the coils do not 

 project out so far from the core as in a three-range. 



Exception is taken to the above by two classes of winding 

 which should be mentioned here. These may be designated 

 respectively: 1. Short-coil windings; 2. Skew-coil windings. 



SHORT-COIL WINDINGS. 



Figs. 232 and 233 show diagrams for two-phase and three- 

 phase short-coil windings. In these windings the coils of the 

 various phases do not overlap, nor their end portions cross one 

 another, but the coils are all of the same size and shape laid on 



13 



