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9. TROUBLESHOOTING
Phenomena Checkpoint Estimated cause Action
Unusual noise is
generated from
the servo
amplifier.
1. If the safe operation is possible,
repeat acceleration/deceleration
4 times or more to complete the
auto tuning.
2. Reduce the auto tuning
response (parameter No.PA09).
1. The servo gain is high.
2. The auto tuning response is high.
Reduce the auto tuning response
and then adjust the gains again.
(Refer to chapter 7.)
If the safe operation is possible,
remove the load and then check
the noise with only the servo
motor.
When unusual noise is generated, the
cause is the bearing life.
Replace the servo motor.
When unusual noise is not generated,
the cause is the backlash increase on
the machine side.
Maintain on the machine side.
Check that the brake is not
dragged for the servo motor with
an electromagnetic brake.
1. The electromagnetic brake release
sequence is incorrect.
2. The power supply for the
electromagnetic brake is faulty.
1. Review the electromagnetic
brake release sequence.
2. Check the power supply for the
electromagnetic brake.
The brake clacks for the servo
motor with an electromagnetic
brake.
This sound is from a clearance of the
brake joint part. This is not a
malfunction.
The servo motor
vibrates.
1. If the safe operation is possible,
repeat acceleration/deceleration
4 times or more to complete the
auto tuning.
2. Reduce the auto tuning
response (parameter No.PA09).
(except the manual mode)
1. The servo gain is too high.
2. The auto tuning response is too
high.
Reduce the auto tuning response
and then adjust the gains again.
(Refer to chapter 7.)
If the safe operation is possible,
execute the adaptive tuning.
The machine vibrates (in sympathy). Adjust the machine resonance
suppression filter.
(Refer to section 8.2)
If the safe operation is possible,
execute the tuning with the
advanced gain search on MR
Configurator MRZJW3-SETUP221
(CS2 or later).
The machine vibrates (in sympathy). Adjust the gains.
(Refer to chapter 7.)
If the safe operation is possible,
execute the tuning with the
advanced vibration suppression
control.
A machine terminal vibrates. Adjust the filter.
(Refer to section 8.4)
Display the cumulative feedback
pulses with the "High speed
monitor" command on the
"Monitor" menu on MR
Configurator. Check the numerical
values are not skipped.
Noises are overlapped in the encoder
cable. This causes miscounting of the
cumulative feedback pulses.
Reduce the noises by setting the
encoder cable apart from the power
supply cable, etc.
Check that the mechanical parts
are not unstable or do not have
backlashes.
The servo motor and the machine
(gear, coupling, etc.) have
backlashes.
Adjust the coupling or the backlash
of the mechanical parts.
Check the mounting part of the
servo motor.
The mounting part of the servo motor
is not enough rigid.
Improve the rigidity by using a
thicker board for the mounting part,
backing up with ribs, etc.
Check the power supply cable of
the servo motor.
An output circuit is open. Review the wiring of the servo
motor power supply cable.
Check that the degree of vibration
changes depending on the motor
speed.
The unbalanced torque is big on the
machine side.
Adjust the balance on the machine
side.
