YASKAWA E-V Series User Manual page 318

Problem Probable Cause
Noise interference due to long serial
converter unit connection cable wir-
ing distance
Noise due to damaged serial con-
verter unit connection cable
Excessive noise to the serial con-
verter unit connection cable
FG electrical potential varies by
Abnormal Noise
influence of such machines on the
from Servomotor
servomotor side as welders.
(cont'd)
SERVOPACK pulse counting error
due to noise
Excessive vibration and shock to
the serial converter unit
Serial converter unit fault
Linear scale fault
Speed loop gain value (Pn100) is
too high.
Position loop gain value (Pn102) is
too high.
Servomotor
Incorrect speed loop integral time
Vibrates at about
constant (Pn101) setting
200 to 400 Hz
Mass ratio data is incorrect.
When the autotuning is used: Incor-
rect mass ratio data setting
Speed loop gain value (Pn100) is
too low.
Position loop gain value (Pn102) is
too high.
Incorrect speed loop integral time
constant (Pn101) setting
High
Speed
Mass ratio data is incorrect.
Overshoot on
Starting and
When the autotuning is used:
Stopping.
Mass ratio data is incorrect.
The force reference is saturated.
The force limit (Pn483, Pn484) is
set to the initial value.
9.3 Troubleshooting Malfunction Based on Operation and Conditions of the Servomotor
Investigative Actions
The wiring distance must be 20 m
max.
Check if the serial converter unit
connection cable is not damaged or
bent.
Check if the serial converter unit
connection cable is bundled with
high-current line or near the high-
current line.
Check if the machine is correctly
grounded.
Check if there is noise interference
on the I/O signal cable from the
encoder.
Check if vibration from the machine
occurred or serial converter unit
installation is incorrect.
(Mounting surface accuracy, or fix-
ing.)
−
−
Check the setting of Pn100 (Speed
Loop Gain).
Check the setting of Pn102 (Posi-
tion Loop Gain).
Check the setting of Pn101 (Speed
Loop Integral Time Constant).
Check the setting of Pn103 (Mass
Ratio).
Check the setting of Pn103 (Mass
Ratio).
Check the setting of Pn100 (Speed
Loop Gain).
Check the setting of Pn102 (Posi-
tion Loop Gain).
Check the setting of Pn101 (Speed
Loop Integral Time Constant).
Check the setting of Pn103 (Mass
Ratio).
Check the setting of Pn103 (Mass
Ratio).
Check the force reference wave
form.
Initial value of force limit:
Pn483 = 30%
Pn484 = 30%
Corrective Actions
Shorten the serial converter unit
connection cable wiring distance to
the specified value.
Modify the serial converter unit
connection cable layout.
Install a surge absorber to the serial
converter unit connection cable.
Ground the machine separately
from PG side FG.
Take measure against noise for the
serial converter unit wiring.
Reduce vibration from the machine,
or correct the serial converter unit
installation.
Replace the serial converter unit.
Replace the linear scale.
Reduce speed loop gain (Pn100)
preset value.
Reduce position loop gain (Pn102)
preset value.
Correct the speed loop integral time
constant (Pn101) setting.
Correct the setting of Pn103 (Mass
Ratio).
Correct the setting of Pn103 (Mass
Ratio).
Reduce the speed loop gain (Pn100)
preset value.
Reduce the position loop gain
(Pn102) preset value.
Correct the speed loop integral time
constant (Pn101) setting.
Correct the setting of Pn103 (Mass
Ratio).
Correct the setting of Pn103 (Mass
Ratio).
Use the mode switch function.
Set a appropriate value for Pn483
and Pn484 (Force Limit).
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