Instruction manual

7. ADJUSTMENT
7.3 Gain Adjustment by Auto Tuning
7.3.1 Adjustment method
In the factory setting of the servo amphfier, auto tuning is valid and the response setting is "2".
The initial settings provide sufficient tuning for general machnes. Higher-level tuning can be provided by
adjusting the response setting (parameter No. 2) according to machme rigichty.
The following table lists guidehes for response setting to drive systems. Choose slow response when using
a reduction gear having backlash:
I
Main Drive System I Fast Response I Middle Response I Slow Response
I
<
I
Ballscrew
Direct coupling
With reduction gear
> <
Direct coupling
> <
With reduction gear
< >
Direct coupling
With reduction gear
< >
Direct coupling
<
With reduction gear
< >
Rack & pinion
< >
Timing belt
Chain
The following is how to adjust the resDonse setting to machme phenomena:
Actual Machine Operation Parameter No. 2 Setting
Ideal Machine Operation
Settling time is long
Increase response setting. Reduce settling time.
I
Large overshoot at stop
I
Decrease response setting.
Set machine selection settine
to "large fixtion". I
Reduce overshoot.
~
Gear sound generated from machme I Reduce gear sound. I Decrease response setting. I
Note: Settling time indmtes time from zero command pulse to servo motor stop.
7.3.2 Valid conditions
If the acceleratioddeceleration time is long or the motor speed used is only
low speed, the vahd conditions of auto tuning are not satisfied. Therefore, it
may result in false tuning.
In ths case, after performing operation whch satisfies the auto tuning
conditions, set parameter No. 20 to "auto tuning not executed".
Ths section provides constraints on the operation pattern to enable excellent auto tuning. If the conditions
in ths section cannot be satisfied, normal auto tuning may not be performed. In ths case, after executing
auto tuning in operation which satisfies the conditions given in this section. make auto tuning invalid to
disallow the gain setting from being changed.
(1) Set the acceleration time (time until the preset speed is reached) to 5s or less and the acceleration/
deceleration current to 50% or more.
(2) Perform operation several times until the cumulative acceleratioddeceleration time is 1s or more.
(3) Set the servo motor speed to 500r/min or more.
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