Re: [CAD_CAM_EDM_DRO] Re: 20 Amp 80 V $99 DC Servodrive

Mariss Freimanis wrote:

> The PID circuit of the G320 is an analog implementation. The
> proportional and derivative co-efficients are set via two screwdriver
> adjustable trimpots marked "GAIN" and "DAMPING" respectively.
>
> Command the motor to turn about 60 RPM and toggle the direction 1 to
> 2 times a second. This will place an impulse load on the motor.
> You set the "GAIN" to the desired stiffness and then adjust
> the "DAMPING" until there is no "ringing" or oscillation.
>
> This is easy to do with the G320. It is tolerant of misadjustment.

Gasp! That may be a good test routine for a motor held securely in a
vise,
but it would be a big mess on my Bridgeport. I had a positioning loop
oscillation in my early setup of my servo amps, and the entire 1800 Lb.
milling machine started to rock from side to side. It was in the range
of 2 Hz. I had to hit E-stop and turn down the gain before trying
again.

Jon