View Single Post
  #43   Report Post  
Posted to uk.d-i-y
Fred Fred is offline
external usenet poster
 
Posts: 78
Default Alcoholic discussion - ac versus dc motors


"The Natural Philosopher" wrote in message
...
Fred wrote:
"The Natural Philosopher" wrote in message
...
Fred wrote:
"The Natural Philosopher" wrote in message
...
Fred wrote:
"The Natural Philosopher" wrote in message
...
Fred wrote:
"The Natural Philosopher" wrote in message
...
The commutator is to ensure the field
in the rotor is aligned wrt the stator to provide continuous
torque. Not sure where you get 3 phase from.
Each winding gets an AC signal. Each winding is switched at 120
degrees phase to the next one: If I told you that and told you
nothing else, you would say 'ah, a 3 phase AC motor!!'

With 3 brushes equally spaced I suppose?
No, three commutator segments spaced equally.
Most motors have far more than 3 commutator segments!


Depends. Most cheap ones have three. Larger motors have more, but
generally at least 5 are in contact with the brushes at any time.


So the brushes are in contact with more commutator segments than the
motor actually has?


It as you that said it had more segments than three, not me.


It was you who said that "generally at least 5 are in contact with the
brushes at any one time"! You also said that most cheap motors had 3
segments.