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DC brushed to AC alternator question

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Active Member
i measured the output performance of quite high input performance DC brushed 7 to 18 V motors and the results were (surprisingly) unsurprisingly poor -- well i have lit some LED-s before ...

the 5-pole(& comm.)-rotor 2-pole stator ones performing 10x better than the 3-pole(& comm.)-rotor 2-pole stator ones
  • ? IF i manage to rebuild commutators to 5- & 3-poles respectively will there be generated volts and/or watts similar to what those things sink
  • ?? assuming the above is done - then - IF i reduce coil impedances - would the small power motors' manetic change oversaturate . . . fast or can they then be used at lower RPM for relatively higher (than for motor INP) OUTP power as the watts/volts lost at coils' resistance reduces
  • ??? WHEN rebuilding the commutators is it making any sense to constantly have coil ends on it's unicue contact ring OR must they be segmented for DC output e.g. is it ...
  • ... possible to convert brushed DC to AC alternator by commutator modification +
  • + the service life does it "pay off" or they're best as they're built - ? MOTORS ?


Well-Known Member
Why go to that bother when you can pick up alternators relatively cheap at auto wreckers.
More efficient than the DC variety.


Active Member
coz i get these motors taking up just a storage space -- 18V+ high amps most above 500mA -- from past cordless drills and hot air blowers (as it comes out the only "quality" part in these things ;) . . . the switches also low ohmic ones o_O)

. . . not very interested of doing this coz it'd take tenon elongate the shaft and the case to cover new contactor or i couldn't use off the shelf carbon brushes . . . not gonna be cheap but likely more powerful than bike dynamo . . . i guess . . .
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Most Helpful Member
Typing with your feet while the spell checker app is turned off? o_O


Active Member
i guess i break down one , replace the carbons with wire contacts , mount a triple fitter on top of the 3 segmented ones and will see , while you can freely complain your dog not accepting the offered food here / end over and out
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