YASKAWA SGD7S-1R9D Product Manual page 534

15.4 Troubleshooting Based on the Operation and Conditions of the Servomotor
Problem
Abnormal
Noise from
Servomotor
15-54
Possible Cause
The Servomotor vibrated
considerably while perform-
ing the tuning-less function
with the default settings.
The machine mounting is not
secure.
The machine mounting is not
secure.
The bearings are defective.
There is a vibration source at
the driven machine.
Noise interference occurred
because of incorrect I/O Sig-
nal Cable specifications.
Noise interference occurred
because an I/O Signal Cable
is too long.
Noise interference occurred
because of incorrect Encoder
Cable specifications.
Noise interference occurred
because the Encoder Cable
is too long.
Confirmation
Check the waveform of
the motor speed.
Turn OFF the Servo Sys-
tem. Check to see if there
are any loose mounting
screws.
Turn OFF the Servo Sys-
tem. Check to see if there
is misalignment in the
coupling.
Turn OFF the Servo Sys-
tem. Check to see if the
coupling is balanced.
Turn OFF the Servo Sys-
tem. Check for noise and
vibration around the bear-
ings.
Turn OFF the Servo Sys-
tem. Check for any for-
eign matter, damage, or
deformation in the
machine's moving parts.
Turn OFF the Servo Sys-
tem. Check the I/O Signal
Cables to see if they sat-
isfy specifications. Use
shielded twisted-pair wire
cables or screened
twisted-pair cables with
conductors of at least
2
0.12 mm .
Turn OFF the Servo Sys-
tem. Check the lengths of
the I/O Signal Cables.
Turn OFF the Servo Sys-
tem. Make sure that the
rotary or Linear Encoder
Cable satisfies the speci-
fications. Use a shielded
twisted-pair wire cable or
a screened twisted-pair
cable with a conductors
2
of at least 0.12 mm .
Turn OFF the Servo Sys-
tem. Check the length of
the Encoder Cable.
Continued from previous page.
Correction Reference
Reduce the load so
that the moment of
inertia ratio or mass
ratio is within the allow-
able value, or increase
page 8-12
the load level or reduce
the rigidity level in the
tuning-less level set-
tings.
Tighten the mounting
–
screws.
Align the coupling.
–
Balance the coupling.
–
Replace the Servomo-
–
tor.
Consult with the
–
machine manufacturer.
Use cables that satisfy
–
the specifications.
The I/O Signal Cables
must be no longer than
–
3 m.
Use cables that satisfy
–
the specifications.
• Rotary Servomotors:
The Encoder Cable
length must be 50 m
max.
• Linear Servomotors:
Make sure that the
Serial Converter Unit
–
Cable is no longer
than 20 m and that
the Linear Encoder
Cable and the Sensor
Cable are no longer
than 15 m each.
Continued on next page.