Re: [CAD_CAM_EDM_DRO] Re: Clarifications needed -

On Friday 12 September 2003 09:44 pm, washcomp spake:

> 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.

Ah, yesssss... okay.
Don't wanna let the smoke out.
They usually don't work after they lose the smoke.

How could I limit the voltage to 79, then?

> > ...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, <snip>

Now I'm confused.
I thought it was either ground from the parallel
port, or +5V from the compueter power supply?

> 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.

I'm not so much looking for "...30 seconds of run-time..." as much
as I'm thinking to try and overcome the *NOTORIOUS* and _frequent_
brown-outs around South Florida.
The half of a second of free spin on the spindle won't really
be horrible, but I'd like to not lose steps and such during one.

> The UPS should be sized to carry all the
> loads for the designed battery life.

Again, just to be clear, I'm not looking to run off of battery power,
but rather avoid lost moves during brief but frequent low voltages.

> If your motor is 3 phase, then
> youl'd need a 3 phase UPS.

110V Rong Fu. (very old Rong Fu)

> 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.

Not that the price of a breakout board bothers me, just that this project got
sidetracked for a year already, and I'm looking to use what I've got, right
now, as I know it's useable.

I've no aversion to purchasing things I find that I
may need to upgrade or otherwise improve upon
afterwards, but want to get things going after such a delay.

Thanks for the input~!

Weyland