Typically the drive needs to be ready and the velocity loop needs to be tuned first before the full closed loop would act normally.
this means two things to start with:
- the offset needs to be adjusted so that the motor is not creeping with the drive enable on and analog setpoint switched to 0V.
- next the drive step response needs to be adjusted so that it reaches the desired speed relatively quickly but no overshooting.
- if the axis runs away uncontrolled after enabling and no adjustments would stop it, this would be a case of bad tach generator feedback.
After the drive is acting ok using the battery box, the analog output and the drive enable from the NC control can be reconnected.
- if you keep getting v-ready off at this point, something else is wrong in the system related to emergency stop and drive enable logic.
- when the axis becomes active and holding position the tuning needs to be completed in closed positioning loop.
- if the axis worked ok with the battery box but running away in closed loop the position feedback is bad, either missing or opposite direction.
- the actual pos. loop gain must be adjusted to match the proposed loop gain (adjust the tach feedback pot to fine tune this)
- the actual pos loop gain need to match between any two axis involved in circular interpolation otherwise the circles comes out oval.
- after the pos loop gain shows correct on both axes, the velocity loop P-gain can be turned up slowly until the motor starts vibrating, then back down to about 80% of that. I know this does not sound very scientific but this is kind of of rule of thumb for field adjustment to achieve reasonably good drive response quickly without a lot of measurements.
- there is a lot more to drive tuning and a lot more can be done in a lab environment but all the above is necessary for a good start in a reasonable time frame.