Mitsubishi Electric MELSERVO-JE Instruction Manual page 70

1. SERVO AMPLIFIER TROUBLESHOOTING
Description
The servo motor vibrates.
Cause
The servo gain is too high. Or
the response of auto tuning is
too high.
The machine is vibrating
(resonating).
The load side is vibrating.
Feedback pulses are being
miscounted due to entered
noise into an encoder cable.
There is a backlash between
the servo motor and machine
(such as a gear and
coupling).
The rigidity of the servo motor
mounting part is low.
The connection of the servo
motor is incorrect.
An unbalanced torque of the
machine is large.
The eccentricity due to a core
gap is large.
A load for the shaft of the
servo motor is large.
An external vibration
propagated to the servo
motor.
Checkpoint
Check if the trouble is solved
by reducing the auto tuning
response ([Pr. PA09]).
If the servo motor can be
driven safely, check if the
trouble is solved by one-touch
tuning or adaptive tuning.
If the servo motor can be
driven safely, check if the
trouble is solved by advanced
vibration suppression control
II.
Check cumulative feedback
pulses using the status
display (only [A]) or MR
Configurator2, and check if its
numerical value is skipped.
Check if there is a backlash
on the machine part.
Check the mounting part of
the servo motor.
Check the wiring of U/V/W.
Check if the vibration varies
depending on the speed.
Check the mounting
accuracy of the servo motor
and machine.
Check the load for the shaft
of the servo motor.
Check the vibration from
outside.
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Action
Adjust gains.
Adjust the machine
resonance suppression filter.
Execute the advanced
vibration suppression control
II.
Please take countermeasures
against noise by laying the
encoder cable apart from
power cables, etc.
Adjust the backlash on the
coupling and machine part.
Increase the rigidity of the
mounting part by methods,
such as increasing the board
thickness and reinforcing the
part with ribs.
Connect it correctly.
Adjust the balance of the
machine.
Review the accuracy.
Adjust the load for the shaft to
within the specifications of the
servo motor.
For the shaft permissible
load, refer to "HG-KN_-
S100/HG-SN_-S100 Servo
Motor Instruction Manual".
Prevent the vibration from the
external vibration source.
Target
[A]
[B]
[C]