Re: [CAD_CAM_EDM_DRO] gecko and power sources

> Sounds like a lot of power on a Sherline. Are you planning to use these
> motors as a spindle motor or actually drive the axis's? I am using 62 vdc
> with some big NEMA 42 sized motors on Bridgett (a 5000+ lbs Bridgeport
> series II) and I would seriously doubt if I am drawing much over 5 amps on
> an ongoing basis. It would take a lot of Sherline machines to equal the
> weight that is getting moved. I run my Shoptask on G320 drives with a 24 vdc
> power supply and again, the table weighs more than a Sherline.
>
> > I have just recieved 2 servo motors off e-bay, and the prelim tests
> > suggest that 10 amps of current at 50-90 volts should be about right.

Indeed, 50 volts at 10 amps is 500 watts, or around 2/3 of a
horsepower. That's well more than the sherline spindle drive. If
these motors will physically fit on the machine (careful not to add
too much weight to the X axis) he can probably run them with a lower
current supply. But it may even make sense to go to smaller motors.

As for the power supply itself, I would be tempted to go buy a 240:120
step down transformer and run the primary off 120 vac to get 60 vac on
the secondary. I know this is not using the transformer as designed,
but my guess is it would work provided one does not try to draw more
current than the device was rated for at 120 volts (ie, secondary
rated 600 VA assuming 120 volts would be 5 amps, don't try to draw
more than that at 60 volts even though 5x60 is only 300 VA because it
is ampere-turns and not voltage that saturates the core)

Chris