Re: Salient Pole Modification

[FutureT-at-xxxxxxx (by way of Terry Fritz <twftesla-at-xxxxxxxxxx>)]

In a message dated 11/9/00 8:56:12 PM Eastern Standard Time, tesla-at-pupman-dot-com 
writes:

> To run at 3000/min,
>  this motor
>  should get 2 flats.
>  My problem is, that I cannot identify any starting windings with thinner
>  wire
>  and also no dead stator poles, i.e. poles without any run windings
>  around them as
>  described in syncmot.zip.
>  How can I determine how many poles the flats in the armature should
>  span?
>  The stator has 24 poles all in all.
>  I think I remember an append of John Freau, wo said, that for a 2 flat
>  motor, the
>  flats should span a maximum of about half the diameter of the
>  armature??? Can
>  anybody confirm or give some more exact value, please.
>  As to the HP: this means horse power, I assume. In Germany we call this
>  PS
>  (Pferdestaerke), a measuements for the power of cars. Now the official
>  measurement
>  ist kW. If 1 HP is equal to 1 PS, my motor would have about 0,6 HP.
>  I'm almost sure, that my assumption HP = PS is correct, but can anybody
>  confirm that?
>  Thanks very much for any advice,
>  Herbert

Herbert,

If your AC in Germany is 3 phase, and if that's a 3 phase motor,
then it won't have a start winding.  3 phase motors are self starting,
and more efficient too.  If it is a 3 phase motor, then I'm not sure
what the flat width should be, I've never modified a 3 phase motor.

If it's single phase, then I've had good results when the flat was
about 1/2 the diameter as you said.  In any case, I never worry
about the dead poles.  Possibly the 3 phase flats should be smaller?

I'm afraid I don't have a definitive answer if this is 3 phase.

You could try a small cut of 1/3 rd the diameter or so at first to
see how it works.

John Freau