Re: [CAD_CAM_EDM_DRO] Sizing a power supply

ptengin@... wrote:

> Jon E.,
> I am running three Applied Motion Products 7080 drives in 1/2 step
> mode.
> I have them connected to an old Northern Telecom 48 volt 40 amp
> supply. I am
> now happy with this setup and was amazed at the improvement in
> performanace
> of the motors when I went from 3-36 volt 10 amps PS's. Since my drives
> are
> rated at 7 amps at 80 volts, I'm interested in building a higher
> voltage PS
> like Jon A. I was thinking of using a 2? KVA buck/boost transformer.
> I'd
> connect 120 volts to the "240 in" terminals. The "120" out would have
> approximately 60 volts out.

That's about 60 V *RMS*.

> Run this through a large bridge rectifier and on
> to large filter caps with bleed resistors. Would this be a workable
> design?
> I'm not real sure what the resultant output voltage would be.

It would be approximately 1.414 * 60 = 85 Volts.

> I thought it
> was somthing like 60 times the square root of 2? I think one could
> vary the
> output voltage slightly if the transformer has 208,220,240 and 277V
> inputs
> taps. An electrical designer I ain't.

Yes, if you have a transformer with the adjustment taps, then you are
set. Otherwise, you
could use a 208/220 volt autotransformer in front of the isolation
transformer to vary
the output voltage.

Jon