Re: Unipolar/Bipolar Parallel/Series?!?!?

--- In CAD_CAM_EDM_DRO@y..., "Weyland" <weyland@v...> wrote:

> Hey Jan~!
>
> Thanks for the info.
> You are making this easier to understand.
>
> I think I have located one of the things that has me confused.
> In the Gecko information sheets it says:
>
> "If a motor is connected in series or full winding,
> the motor's phase current rating is half of its parallel or unipolar
> rating."
>
> This seems to me (bearing in mind *my* ingnorance) to be
> mixing two different methods, no?
>
> Since I am going for bipolar, I know now that I have two choices.
> (Series and parallel for the two phases/four windings)
> How does the statement above reconcile with this knowledge.
> I know I should see this clearly, but I just don't.
> Likewise about the 5.0A bipolar rating on the motor.
> Is that series or parallel?
>
> And how would running a motor in series
> bipolar equal to the current rating of unipolar?
>
> And if I'm interpetting the above correctly, does
> that mean that the parallel bipolar configuration is the 5.0A rated

one?

> How then is that possible if parallel is supposed to be *twice* the

current?

>
> Gadz, I'm drowning now...

When Mariss wrote this, surely he was experiencing a taste of the
grape! the 5 amp (in this motor's case) is "parallel", and the 3.5
is for ONE-half of each center-tapped winding, this center-tap being
just the connection between two of the four windings in the motor.
Never 3.5 amp through BOTH halves of either or both center-tapped
winding at the same instant. I.e., "one half the copper unused" at
any instant. The disadvantage of unipolar! Why bipolar is better!
(Also, you have INDUCED current in the "unused" half, which
is "wasted", etc. NOT a good plan,that old unipolar configuration!)

You see, since one half the copper is "idle" at any instant, the one
conducting half can handle "more than half the 5.0 amp", or, 3.5
amp. But I suggest you just wire for bipolar (two pairs of
parallelled windings) and know that is best, and ignore all
this "theory" stuff! It confuses me, and makes me wish I had access
to Mariss' bottle of the vintner's magic!