RE: [CAD_CAM_EDM_DRO] half step shaping was Re: Newbie question. Second try

Hi, Alan:

I was weeding out old messages, came across this one, and had a question, so
here goes

|Let me quote from an earlier post from Mariss:
|
|
|" Here are the rules:
|
|4-wire motor. No problem. Use the rated current and you will be fine.
|No options here.

Understand this one.

|6-wire motor (unipolar). This is the same as the 4-wire except the
|windings are center-tapped and the center taps are brought out.

|You have two choices here; half-winding or full winding. You use half-
|winding if yours is a high speed application or full winding if it is
|a low speed one. Use the unipolar current rating for half-winding and
|1/2 that for full winding.

Don't understand this. It would seem that, when used in unipolar mode, you'd
connect the taps to the + voltage and the ends to the driver transistor
collectors. And, you'd set the series resistor to drive the "rated" current
through the coils. Right?

And, for bipolar, you'd either drive half the coil at full current, or the
full coil at half current rather than as you've stated. It would seem to me
that you'd want to maintain the same number of amp-turns for each coil
regardless of whether you were using the full coil, or half of the full
coil. Where am I missing it?

-- Carol & Jerry Jankura
Strongsville, Ohio
So many toys, so little time....