Troubleshooting Of Warnings - YASKAWA Σ-V Series User Manual

8.2.2 Troubleshooting of Warnings

Refer to the following table to identity the cause of a warning and the action to be taken. Contact your
Yaskawa representative if the problem cannot be solved by the described corrective action.
Warning
Warning Name
Display
Position Error
A.900
Pulse Overflow
Position Error
Pulse Overflow
A.901
Alarm at Servo
ON
Overload:
Warning before
A.910
alarm A.710 or
A.720 occurs
A.911 Vibration
Situation at Warning
Occurrence
Wiring of the linear ser-
Check the wiring of the cable for lin-
vomotor U, V, or W line
ear servomotor main circuit.
is incorrect.
The SERVOPACK gain
Check the SERVOPACK gain.
is too low.
The position reference Lower the position reference acceler-
acceleration is too high. ation.
The excessive position
error alarm level
Check the excessive position error
(Pn520) is too low for
alarm level (Pn520).
the operating condi-
tions.
A SERVOPACK fault
−
occurred.
When the linear servo-
motor power was OFF,
the linear servomotor
moved without clearing
the counter for position Check the error counter (Un008) in
error pulses. The num- servo OFF state.
ber of position error
pulses exceeded the
maximum number of
pulses allowed.
The linear servomotor
or linear scale wiring is
Check the wiring.
incorrect or the connec-
tion is faulty.
The linear servomotor is
Check the overload characteristics of
in excess of the over-
the linear servomotor and reference
load protective charac-
input.
teristics.
The linear servomotor is
not driven due to a
Check the reference input and motor
mechanical factor and
speed.
the operating load has
become excessive.
A SERVOPACK fault
−
occurred.
Abnormal vibration was Check whether unusual sound is gen-
detected while the linear erated from the linear servomotor,
servomotor was mov- and check the speed and force wave-
ing. form of the linear servomotor.
The mass ratio (Pn103)
is larger than the actual
Check the mass value.
value or greatly
changes.
Cause
Check whether there is any loose con-
nection in linear servomotor wiring or
linear scale wiring.
Increase the servo gain by using the
function such as advanced autotuning.
Apply a smoothing function, such as a
position reference acceleration/decel-
eration time constant (Pn216).
Set an appropriate value for the
Pn520.
Turn the power supply OFF and then
ON again. If the alarm still occurs, the
SERVOPACK may be faulty. Replace
the SERVOPACK.
Make the setting so that the position
error pulse is cleared when the linear
servomotor power is OFF.
Or, set an appropriate value for the
excessive position error warning level
at servo ON (Pn528).
Correct the linear servomotor and lin-
ear scale wiring if they are wrong.
Reconsider the load and operation
conditions.
Or, check the linear servomotor capac-
ity.
Improve the mechanical factor.
The SERVOPACK may be faulty.
Replace the SERVOPACK.
Lower the motor speed or the lower
the servo gain by using the function
such as one-parameter tuning.
Set an appropriate value for the mass
ratio (Pn103).
8.2 Warning Displays
Corrective Actions
8-25
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