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68
HA0364T Rev C Aug 2022
Chapter 6
Absolute Position Reporting Mode
This setting relates to the way in which the angular position is displayed on the GUI
panel. There are two options:
Equivalent Angle 0 to 360 degrees
– The maximum displayed position is 359.99°.
If a stage is driven past the 360° rotation point, the display reverts back to zero
and counts up to 360° again.
Total Angle (360 x Num Revs + Angular Offset) –
The total angular rotation is
displayed, e.g. for a movement of two full rotations plus 10°, the display will show 730°.
Note
. The following parameters are applicable only if the Absolute Position
Reporting Mode is set to
‘
Equivalent Angle 0 to 360 degrees
’
.
Panel Display Rotation Move Mode
This setting specifies the move direction. There are three options:
Rotate Positive
– The move is performed in a positive direction
Rotate Negative
- The move is performed in a negative direction
Rotate Quickest
- The move is performed in the quickest direction
6.4 Troubleshooting and Restoring Default Parameters
Position PID Settings Summary
Stage overshoots the intended position
- reduce the integral term, and increase the
derivative and proportional terms.
Stage fails to attain final position
- increase the integral and proportional terms.
Motion is unstable
- reduce the prop and int terms, increase the derivative term.
Stage sounds noisy
- reduce the derivative term.
See Section 6.3.3. for further information.
Caution
The PID and other closed loop parameters must be set according to the
stage or actuator type associated with the driver, the load being
positioned and the speed/duty cycle of operation. Default values have
already been optimized and stored within the stage, and these are loaded
into the driver on power up.
If problems are encountered (e.g. stability of the closed loop position
control, lost motion or incomplete moves) the position PID parameters
should be adjusted to tune the stage for the given application. Normally,
only minor adjustment of the Proportional, Integral and Derivative
parameters should be necessary, and some trial and error will be required
before the ideal settings for a specific application are achieved. In cases
where further adjustment of the control loop parameters is required, the
following guidelines are provided in order to assist in the tuning process.