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DC electric motor

DC electric motor

DC electric motor

Hi. Can someone confirm that adjacent commutator segments SHOULDN'T read zero ohms ?
I just received a replacement armature for a small starter motor, and almost immediately noticed that the cuts to separate the segments don't look like they go all the way through the copper. I don't have a milli-ohmmeter for a precise measurement, but I am fairly sure that only opposite segments should connect together through the (single turn) windings.


RE: DC electric motor

It is really hard to read resistances as low as you should have with a DVM.
Most commutators have insulating material between the bars. Adjacent commutator bars are "electrically close"


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