YASKAWA SGD7S-R70A Product Manual page 195

Problem Possible Cause
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.
Abnormal
Noise interference occurred
Noise from
because of incorrect Encoder
Servomotor
Cable specifications.
Noise interference occurred
because the Encoder Cable
is too long.
Noise interference occurred
because the Encoder Cable
is damaged.
The Encoder Cable was sub-
jected to excessive noise
interference.
8.3 Troubleshooting Based on the Operation and Conditions of the Servomotor
Confirmation
Turn OFF the power sup-
ply to the servo system.
Check for noise and
vibration around the bear-
ings.
Turn OFF the power sup-
ply to the servo system.
Check for any foreign
matter, damage, or defor-
mation in the machine's
moving parts.
Turn OFF the power sup-
ply to the servo system.
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 power sup-
ply to the servo system.
Check the lengths of the
I/O signal cables.
Turn OFF the power sup-
ply to the servo system.
Make sure that the rotary
or Linear Encoder Cable
satisfies the specifica-
tions. Use a shielded
twisted-pair wire cable or
a screened twisted-pair
cable with a conductors
of at least 0.12 mm
Turn OFF the power sup-
ply to the servo system.
Check the length of the
Encoder Cable.
Turn OFF the power sup-
ply to the servo system.
Check the Encoder Cable
to see if it is pinched or
the sheath is damaged.
Turn OFF the power sup-
ply to the servo system.
Check to see if the
Encoder Cable is bundled
with a high-current line or
installed near a high-cur-
rent line.
Continued from previous page.
Correction
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.
2
.
• 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.
Replace the Encoder
Cable and correct the
cable installation envi-
ronment.
Correct the cable lay-
out so that no surge is
applied by high-current
lines.
Continued on next page.
Reference
–
–
–
–
–
–
–
–
8
8-55