A cikin injinan fan na mota, ramin commutator nau'in mai haɗawa ne na gama gari. Ya ƙunshi ƙayyadaddun zobe mai ɗawainiya da adadin goge-goge, yawanci ana sanya su a tsaka-tsaki na yau da kullun a cikin ramummuka akan stator na motar.
Ƙarfin wutar lantarki na graphite yana da kyau sosai, ya zarce ƙarfe da yawa da ɗaruruwan lokuta na waɗanda ba ƙarfe ba, don haka ana ƙera shi zuwa sassa masu sarrafawa kamar electrodes da brushes na carbon;
Takamaiman rawar carbon goga
NdFeB maganadiso a halin yanzu sune mafi ƙarfi na dindindin maganadisu.
