Mitsubishi Electric MR-J2-03B5, Instruction Manual

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6. ADJUSTMENT
6.4.3 Load inertia moment is 20 or more times
(1) Machine condition
The machine inertia moment is 20 times or more and the servo motor oscillates at low frequency (5Hz
or more). At this time, servo motor shaft vibration can be confirmed visually.
This adjustment method is valid for the following machines:
(a) Machine in which a timing belt is driven without reduction gear
Servo motor
Pulley
(b) Machine in which a disc is rotated without reduction gear
Servo motor
Disc
(c) Machine of which ballscrew lead is long
Ballscrew
Servo motor
(2) Adjustment procedure
1) Select the response selection of low response.
Set parameter No. 8 to "0001" and parameter No. 9 to "0003" or less.
2) Set the load inertia moment ratio (parameter No. 12).
If an exact load inertia moment ratio is unknown, enter an approximate value.
When the value is set in this parameter, the following parameters are set automatically. When
there is no machine resonance, the value of each parameter is set to the ideal gain for the load
inertia moment ratio (parameter No. 12) value.
Parameter No. Symbol Name
13 PG1 Position loop gain 1
15 PG2 Position loop gain 2
14 VG1 Speed loop gain 1
16 VG2 Speed loop gain 2
17 VIC Speed integral compensation
3) Set "not executed" (parameter No. 8 to 0002) by the auto tuning selection.
4) Alternate a start and a stop several times and check whether the machine does not vibrate.
5) If vibration still persists, repeat steps 1) to 4).
6) If vibration still persists, make (a) adjustment 1 and (b) adjustment 2 in paragraph (2) of Section
6.4.2.
7) To further increase the response, set auto tuning selection to Valid (parameter No. 8: 0001) with
operation at a stop, and increase the response setting (parameter No. 9).
After that, set auto tuning to "Not executed" (parameter No. 8: 0002).
8) Reducing the speed loop's integral compensation (parameter No. 17) may improve the perform-
ance. However, making it too small may generate vibration.