YASKAWA SGD7S series Product Manual page 536

12.4 Troubleshooting Based on the Operation and Conditions of the Servomotor
Problem
Servomotor
Vibrates at
Frequency
of Approx.
200 to 400
Hz.
Large Motor
Speed
Overshoot
on Starting
and Stop-
ping
Absolute
Encoder
Position
Deviation
Error (The
position
that was
saved in the
host con-
troller when
the power
was turned
OFF is dif-
ferent from
the posi-
tion when
the power
was next
turned ON.)
12-60
Possible Cause
The servo gains are not bal-
anced.
The setting of Pn100 (Speed
Loop Gain) is too high.
The setting of Pn102 (Posi-
tion Loop Gain) is too high.
The setting of Pn101 (Speed
Loop Integral Time Con-
stant) is not appropriate.
The setting of Pn103
(Moment of Inertia Ratio or
Mass Ratio) is not appropri-
ate.
The servo gains are not bal-
anced.
The setting of Pn100 (Speed
Loop Gain) is too high.
The setting of Pn102 (Posi-
tion Loop Gain) is too high.
The setting of Pn101 (Speed
Loop Integral Time Con-
stant) is not appropriate.
The setting of Pn103
(Moment of Inertia Ratio or
Mass Ratio) is not appropri-
ate.
The torque reference is satu-
rated.
The force limits (Pn483 and
Pn484) are set to the default
values.
Noise interference occurred
because of incorrect Encoder
Cable specifications.
Confirmation
Check to see if the servo
gains have been cor-
rectly tuned.
Check the setting of
Pn100.
The default setting is Kv =
40.0 Hz.
Check the setting of
Pn102.
The default setting is Kp
= 40.0/s.
Check the setting of
Pn101.
The default setting is Ti =
20.0 ms.
Check the setting of
Pn103.
Check to see if the servo
gains have been cor-
rectly tuned.
Check the setting of
Pn100.
The default setting is Kv =
40.0 Hz.
Check the setting of
Pn102.
The default setting is Kp
= 40.0/s.
Check the setting of
Pn101.
The default setting is Ti =
20.0 ms.
Check the setting of
Pn103.
Check the waveform of
the torque reference.
The default values of the
force limits are Pn483 =
30% and Pn484 = 30%.
Check the Encoder Cable
to see if it satisfies speci-
fications. Use shielded
twisted-pair cables or
screened twisted-pair
cables with conductors of
2
at least 0.12 mm
(stranded wire).
Continued from previous page.
Correction Reference
Perform autotuning
without a host refer-
page 8-24
ence.
Set Pn100 to an appro-
–
priate value.
Set Pn102 to an appro-
–
priate value.
Set Pn101 to an appro-
–
priate value.
Set Pn103 to an appro-
–
priate value.
Perform autotuning
without a host refer-
page 8-24
ence.
Set Pn100 to an appro-
–
priate value.
Set Pn102 to an appro-
–
priate value.
Set Pn101 to an appro-
–
priate value.
Set Pn103 to an appro-
–
priate value.
Use the mode switch.
–
Set Pn483 and Pn484
page 6-63
to appropriate values.
Use cables that satisfy
–
the specifications.
Continued on next page.