
B-65280EN/05 FANUC AC SPINDLE MOTOR αi series 4.ADJUSTMENT
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compensation parameter (parameter No. 4356 or 4358).
Typically, set a value with which the amplitude of averaged
incremental data is minimized. First, check the amplitude by
entering (+)1 as the parameter value and the amplitude by
entering -1. In the direction in which the amplitude becomes
smaller, change the parameter value in steps of 1. Then, you can
find the optimum value easily. Fig. 4.3.3 shows the waveform
obtained after phase difference compensation adjustment.
CH1:(313.4.0.1)
Feedback increment
0.5V/div
CH2:(231.8.0.0)
Feedback data
5V/div
Time range:5ms/div
32 averaging times
0.57V
Fig. 4.3.3 After phase difference compensation
<4> Adjusting the amplitude ratio compensation parameter
After adjusting phase difference compensation to an optimum
value, adjust amplitude ratio compensation. The adjustment
method and the guideline for adjustment are the same as for
phase difference compensation. Perform adjustment so that the
amplitude of feedback incremental data becomes smaller. Fig.
4.3.4 shows the waveform obtained after adjustment of amplitude
ratio compensation (and phase difference compensation).
CH1:(313.4.0.1)
Feedback increment
0.5V/div
CH2:(231.8.0.0)
Feedback data
5V/div
Time range:5ms/div
32 averaging times
0.42V
Fig. 4.3.4 After amplitude ratio (and phase difference) compensation
NOTE
Whichever compensation, amplitude ratio
compensation or phase difference compensation,
may be adjusted first, the same adjustment result
can be obtained. So, steps <3> and <4> may be
performed in reverse order.