Twentieth century hand-book for steam engineers and electricians, with questions and answers .. (1905)
Swingle, C. F. [from old catalog], Horstmann, Henry Charles, 1858- [from old catalog], Tousley, Victor Hugo, 1875- [from old catalog] · Chicago, F. J. Drake & co. · leaf 482
uit, but this method shouldonly be used in emergency, as the sparking will in timedestroy the commutator. With many dynamos, especially of older types, it isnecessary to shift the brushes with every change ofload. The current produced by the armature makes amagnet out of it and the magnetism of the… … FIGURE 35. of the armature. In Fig. 36 we assume a heavy loadon the dynamo and consequently the magnetism of thearmature opposes that of the fields. This changes thelocation of the neutral point (when the coils under thebrush generate no current) and it becomes necessary to
