Chapter 7 Special Adjustment Functions - Mitsubishi Electric MELSERVO-J4 Series Instruction Manual

7
SPECIAL ADJUSTMENT FUNCTIONS
• The functions given in this chapter need not be used normally. Use them if you are not satisfied with the
machine status after making adjustment in the methods in the following chapter. Page 227 NORMAL
GAIN ADJUSTMENT
• When you use a linear servo motor, replace the following left words to the right words. Load to motor inertia
ratio  Load to motor mass ratio
Torque  Thrust
7.1
Filter setting
The following filters are available with MR-J4 servo amplifiers.
+
Command
Command
filter
pulse train -
Machine resonance suppression filter
• The machine resonance suppression filter is a delay factor for the servo system. Therefore, vibration may
increase if you set an incorrect resonance frequency or set notch characteristics too deep or too wide.
• If the frequency of machine resonance is unknown, decrease the notch frequency from higher to lower ones
in order. The optimum notch frequency is set at the point where vibration is minimal.
• A deeper notch has a higher effect on machine resonance suppression but increases a phase delay and
may increase vibration.
• A wider notch has a higher effect on machine resonance suppression but increases a phase delay and may
increase vibration.
• The machine characteristic can be grasped beforehand by the machine analyzer on MR Configurator2. This
allows the required notch frequency and notch characteristics to be determined.
If a mechanical system has a natural resonance point, increasing the servo system response level may cause the mechanical
system to produce resonance (vibration or unusual noise) at that resonance frequency. Using the machine resonance
suppression filter and adaptive tuning can suppress the resonance of the mechanical system. The setting range is 10 Hz to
4500 Hz.
Speed
[Pr. PB18] [Pr. PB13]
control
Machine
Low-pass
resonance
filter
suppression
setting
[Pr. PB48]
[Pr. PB49]
Machine
resonance
suppression
filter 4
[Pr. PB17]
Shaft
resonance
suppression
filter
[Pr. PB15]
Machine
resonance
suppression
filter 1 filter 2
[Pr. PB50]
[Pr. PE41]
Machine
resonance
suppression
filter 5
Robust filter
7 SPECIAL ADJUSTMENT FUNCTIONS
[Pr. PB46]
Machine
resonance
suppression
filter 3
Load
Encoder
M
PWM
Servo motor
7.1 Filter setting
7
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