8.12 Additional Adjustment Functions
8.12.6 Speed Detection Method Selection
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8
T
uning
8.12.6
Speed Detection Method Selection
You can use the speed detection method selection to ensure smooth Servomotor speed
changes during operation. To ensure smooth motor speed changes during operation, set
Pn009 to n.
1
(Use speed detection 2).
With a Linear Servomotor, you can reduce the noise level of the running motor when the linear
encoder scale pitch is large.
8.12.7
Speed Feedback Filter
You can set a first order lag filter for the speed feedback in the speed loop. This ensures
smooth changes in the feedback speed to reduce vibration. If a large value is set, it will
increase the delay and make response slower.
8.12.8
Backlash Compensation
Outline
If you drive a machine that has backlash, there will be deviation between the travel distance in
the position reference that is managed by the host controller and the travel distance of the
actual machine. Use backlash compensation to add the backlash compensation value to the
position reference and use the result to drive the Servomotor. This will ensure that the travel
distance of the actual machine will be the same as the travel distance in the host controller.
Note: Backlash compensation can be used only with a Rotary Servomotor.
If the current gain level is changed, the response characteristic of the speed loop will also
change. Servo tuning must therefore be performed again.
Important
Parameter
Meaning
When Enabled
Classification
Pn009
n.
0
(default setting)
Use speed detection 1.
After restart
Tuning
n.
1
Use speed detection 2.
If the speed detection method is changed, the response characteristic of the speed loop will also
change. Servo tuning must therefore be performed again.
Important
Pn308
Speed Feedback Filter Time Constant
Setting Range
Setting Unit
Default Setting
When Enabled
Classification
0 to 65,535
(0.00 ms to 655.35 ms)
0.01 ms
0
(0.00 ms)
Immediately
Setup
Reference travel distance
Machine shaft
Backlash compensation value
Reference travel
distance
Motor shaft
Forward reference direction
Motor shaft
Machine axis (e.g., table)
Backlash (play due to mechanical tolerance)