Re: Clarifications needed -

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Weyland <weyland@v...> wrote:

> Hi All~!
>
> Trying to finish up my conversion tonight or
> tomorrow, but need some things clarified before I can.
>
> First - Geckos and voltage.
> My power supply is putting out 82.6 VDC.
> And I've wired the Geckos in the "star" configuration recommended.
> My concern is over the 80 VDC limit for the Geckos.
> (G210s marked with "90IFX" on the covers.)

I'm going to assume that Mariss Freimanis of Gecko would have
labeled them 90 volts instead of 80 volts if it was safe to use 90
volts. You're not pushing the envelope, you are probably outside
the box and may let the smoke out of your Geckos.

>
> Second, I'm confused about the capacitors one
> might or might not use on the Geckos themselves.
> My power supply is pretty close to the
> Geckos, but the motor cables run 10 feet long.
> Do I need capacitors? Which size?

Capacitors are cheap, and can't hurt. I forget the size that are
recommended, but I think they are described in the application white
paper on the Gecko site.

>
> Third - the +5V.
> Assuming that I want to work with what I have right now and not

need to

> spend more money, do I get that +5V from the computer power supply
> or does it come from somewhere in the parallel port?

Assuming you are using a parallel port breakout board, it should be
supplying the appropriate five volts. As parallel port output is
5volt TTL level, I don't know that its enough for the motors, but
I'll let others comment more here as its not my field of expertise.
I thought a breakout board was a worthwhile investment so I didn't
dwell on its design beyond satisfying myself that it would work.

>
> And Fourth, I'm planning on using a UPS for the controller, and

wanted

> to know people's thoughts on using it for the motor's power supply

as well.

I don't think its a problem (a decent UPS will output a pretty good
sine wave so the PS should see it as AC). Most small UPS's will
only run off the inverter when the AC power is cut. Be aware that
if you are trying to give yourself time to shut down during a
blackout, keeping the steppers moving, but letting your spindle stop
could create a load and flashy demise for your machine, your work or
anyone standing nearby. The UPS should be sized to carry all the
loads for the designed battery life. If your motor is 3 phase, then
youl'd need a 3 phase UPS. They are available, but if the cost of a
parallel breakout board bothers you, your safer letting the PS to
the steppers shut off with the spindle than the shock to your heart
of the price of the UPS.

>
> Thanks,
>
> Weyland

Regards,
Jeff