Re: [CAD_CAM_EDM_DRO] Re: Wanted: Servo Motors that interface to Gecko 320-Ron

John Meissner wrote:

>Hi Ron,
> I'm just wondering if you are using a "dump" circuit to drain off
>the back voltage when slowing the motors rapidly? I'll be using a
>75VDC supply and after what you say about the 118VDC breakup point,
>would a dump be absolutely necessary?
>
>

Assuming a mid-sized machine and typical motors, and the recommended
size of filter capacitors in the power supply, it probably is not necessary.
I did some measurements, and rapid stops even on multiple axes at the same
time only caused the power supply voltage to rise about 2 volts. A very
heavy machine with minimal friction, very low resistance motors, and small
filter caps on the power supply could make the rise greater. You can always
set it up, and put a voltmeter on the supply. Accelerate and slow down
first one
axis, then two at a time, then three. If the voltage surges higher than
you feel
safe, then get the dump circuit.

Jon