[Electric engineering.] . etween a d is equal to that between b e and the machines aredelivering equal currents, then the drop through a d will 74 ELECTRIC TRANSMISSION. 15 equal the drop through be and points a and b will be atthe same potential. Since current can only flow betweenpoints at different potentials, there will be no current in Eunder such circumstances. Suppose, however, that Adelivers a greater current than B; then the drop in a dwill exceed that in b e and current will flow through thepath a-E-b-f-M-e and thus build up the voltage ofmachine B and equalize the load. If B deliver
[Electric engineering.] . etween a d is equal to that between b e and the machines aredelivering equal currents, then the drop through a d will 74 ELECTRIC TRANSMISSION. 15 equal the drop through be and points a and b will be atthe same potential. Since current can only flow betweenpoints at different potentials, there will be no current in Eunder such circumstances. Suppose, however, that Adelivers a greater current than B; then the drop in a dwill exceed that in b e and current will flow through thepath a-E-b-f-M-e and thus build up the voltage ofmachine B and equalize the load. If B delivers more cur-rent than A, the drop in be exceeds that in ad and currentflows through the path b-E-a-c-M-d, builds up the voltageof A, and makes A take its share of the load. 85. In Fig. 60, the equalizer E is shown as connectingthe positive brushes. This is usually the case in practice,though it would work just as well if both a and b were nega-tive brushes and c,f the negative terminals of the machines. Fie/d RheosfafA/o /. f/e/af f?/?eosfafA/o. 2 Fig. 61. The only thing that must be looked out for is to see that theequalizer connects the brushes to which the series coils areattached, and also to see that these brushes are of the samepolarity. In some cases, the equalizer wire is run directly §15 ELECTRIC TRANSMISSION. 75 between the machines, as shown, but often a third wire isrun from points a and b to the switchboard and there con-nected to an equalizer bar, as shown in Fig. 61. This repre-sents a very common arrangement, triple-pole switchesbeing used; the two outside blades for the -f- and — leadsand the middle blade for the equalizer. There is a differ-ence of opinion as to whether it is better to run the equal-izer to the switchboard or run it directly between the To—bus baron sw//cbboard
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