Følgende er skrevet af Phil Allison:
"Bob C"

I have an old 12 volt 3 phase model railroad motor


** You mean 12volt 3 pole ?

Typically, 12 volt DC motors have 5 poles - with only three, arcing across
the comm segments will be severe with 12V input.

Depends.

The model racing cars my dad imported while I was a kid (Jouef) had 3
poles, while the trains, especially the higher class models, had 5
poles, to be able to drive more slowly and smoothly.

Leif

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