Re: Want to convert step-pulley drive to digital speed control

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "caudlet" <thom@t...> wrote:

> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "Steve" <s_hight@y...> wrote:
> > --- In CAD_CAM_EDM_DRO@yahoogroups.com, "caudlet" <thom@t...> wrote:
> > > --- In CAD_CAM_EDM_DRO@yahoogroups.com, "Robert Campbell" <bob@c...>
> > > wrote:
> > > > Steve,
> > > >
> > > > A VFD (Variable Frequency drive) may work. Look at Automation
> > Direct.
> > > > WWW.automationDirect.com
> > > >
> > > > If a VFD will work, then using one of our spindle speed control
> > > boards would
> > > > give you control from your program.
> > > >
> > > > At least that would be a place to start looking.
> > > >
> > >
> > >
> > > AND the VFD will take the place of the static converter and give you
> > > back full power on the motor as well as speed control. Feed it
> > single
> > > phase 230VAC 50/60HZ and like magic you get 3ph out at varying
> > frequency.
> >
> > This is excellent! It looks like the model I need is the GS2.
> > http://web5.automationdirect.com/adc/Shopping/Cata
> > log/AC_Drives_-z-_Motors/GS2_(115_-z-_230_-z-_460_
> > VAC_V-z-Hz_Control)/GS2-23P0
> >
> > At 325.00 it seems like a heck of a deal. I am going to order one.
> >
> > Thanks for the help!
> >
> > Steve
> \
> Just make sure the VFD can be controlled with an exernal analog
> voltage. 0-10VDC is common and so is 0-5VDC. Then all you have to do
> is interface it through one of the Campbell Cards with the motor speed
> option card and you can "command" the spindle speed in MACH2.

It looks like it meets that spec. From the manual the analog
interface specs are listed as:

1 user-configurable, 0 to 10VDC (input impedance 10k), 0 to 20mA, 4 to
20mA (input impedance 250), 10 bit resolution