Re: [CAD_CAM_EDM_DRO] Servo Rotating Problem

Imran Jawaid wrote:

>
> I've stopped 2 axes rotation till 0.000x of an inch by adding
> insulation , ground
> but the third axes still keeps rotating , how can i use the Bias
> adjustment, i tried to give it
> values like 4 & -4 but didn't work

When you say it is "still rotating" how fast do you mean? If it is
just creeping very slowly, that is normal, and really shouldn't be
a problem. If it is really spinning, then you most likely have the
DC tach wired backwards (when in Estop-off mode, the only
feedback is from the tach).

> Also when I go to Machine ON mode the Motor/s takes a jerk & emc
> gives error
> "Axis x following error" , x=0,1or2.
> How can i get in the Machine ON state

If the error band is set too tight, then it can't get past this transition
(from position open-loop to closed loop). The following error
limits should be set to something like .050" to start out with.
If this is defined as a metric machine, that could be a problem.
I know pretty much how it works in imperial units, but there could
be some conversion problems with metric. Anyway, just try
increasing the following error limit to a significant distance.
Now, when you make the transition to machine on, do the motors
travel that distance? You can read the position on the absolute
or relative actual displays. If the motors actually travel some
large distance, then you have a mixup in the + / - movement
directions. There are many polarities that have to be set
properly. The 'polarity' of the encoder can be set in the .ini file
to get proper counting of the machine coordinates. Then, the
polarity of the velocity commands from the STG's DACs need
to properly match the servo amp input. My amps are differential-in,
so I can swap the leads to reverse this polarity. If you can't do
that, you may need to reverse both the motor and tach wires.
Finally, if the motor and tach wires are not consistant, the servo
amp will immediately drive the motor at full speed one way or
the other as soon as they are enabled. (I think you have gotten
past this, but I'm not sure.)

Jon