Re: [CAD_CAM_EDM_DRO] Help identifying a stepper motor please

> It is an 8 lead stepper, with four of the leads taped up and
> individually isolated (Pink, Yellow, Blue, Orange) and is driven on
> the other four (Grey, Red, Black, White)
>
> I'm somewhat puzzeled by the lead configuration but don't want to
> pull it all apart just yet as it's working.

An eight wire motor has each of the two phases split into two
electrically seperate coils. To use it unipolar, you connect the
two coils in series to make a center tapped phase.

To use it bipolar you connect them in parallel to make a single
bipolar winding.

Or you connect them in series and make a high inductance winding
(not a good idea)

Or you simply use only one of the two coils for each phase.

This last case seems to be how your machine is set up. It's not a bad
way to go - you may be able to get a slight benefit by going to
parallel configuration, but not much. And you would have to be sure
you wired the coils in parallel instead of anti-parallel (ie, the
current must flow in the same direction with respect to the way the
wire is wound).

Sorry I can't help with figuring out the allowable current limit.

Chris