Re: [CAD_CAM_EDM_DRO] Re: Spindle Relay Question

David,
Just make sure that the drive is not energized when you swap leads, or
you will very likely fry the VFD.

I'm not sure what you will use for a 0-10V precision DC output source,
though -- those are not standard outputs on a typical PC Outputs like
that usually come from a digital to analog converter card -- not that
hard to find, but certainly not a standard peripheral.

DPDT relays are readily available on eBay - you need only choose one
with contact ratings 50% over the typical current draw of your motor,
and a coil suitable for the drive output of your computer. You will
probably have to use some sort of transistor or solid state relay to
boost the TTL outputs of a typical computer output port to a level that
will drive a typical power relay.. A small solid state relay driving
the coil of the large power relay would fill the bill. I do not,
however, know of any solid state relays that would do the power lead
switching directly, at least not at an inexpensive price.

Dave Speck

volitan712003 wrote:

>Whoa nelly did I botch that post!
>
>Let me be more clear. The drive will accept a 10 volt analog signal to
>control the speed, so controlling the spindle via computer is no
>problem.
>
>The drive will not reverse the motor. The only way to do that is swap
>the 2 power wires going to it (the motor). That's why I'm after (I
>think) a DPDT relay. Just can't find one. Or else if anyone has any
>better idea...
>
>Sorry for the confusion
>
>David
>
>
>