Re: [CAD_CAM_EDM_DRO] driver wiring questions

Al Schoepp wrote:

> Hi
>
> I'm fairly new to all this and I have a few questions. I thought I'd ask
> here rather than pestering Dan/Mariss at Camtronics/Gecko and there might
> be other beginners here who would appreciate the answers. I'm using
> G201A's to power a Taig mill (still waiting for the mill to show up). I've
> managed to round up a 24V 10A transformer.
>
> According to the instructions from Gecko I will need a minimum of about
> 24,000 microfarad cap.
>
> 80,000*10/33.6=23809
>
> How critical is this, I have a 20,000 75v cap on the bench and would just
> as soon use that.

It is not very critical at all. Try the 20,000 uF cap. You can use a DVM on
the
AC setting to see how much voltage ripple you get. If it is more than 5 V,
then
you should increase the cap value.

> The steppers I'm using are p/n 1523-025, 210 oz.in., from Camtronics. They
> can obviously be wired for series (2A) or parallel (4A). I'm planning on
> series, the thought being that if things go well I may put on a fourth axis
> and the 10A power supply may not be enough for 4 axis at 4A. Comments?

The stepper will have poor performance with the windings in series, as the
inductance
goes up 4 x that way. In fact, the current draw from the power supply will be
about
the same, as the I^2*R loss is about the same either way, at rated current.
This is because
the G201 is a switching power supply, and will have to have the transistors on
2x longer
with the series winding than with the parallel, and this exactly compensates
for the
lower current. The power draw when moving is harder to figure, but will
likely be
nearly the same, too.

Jon