Yaskawa Sigma-5 User Manual: Design and Maintenance - Linear Motors - Manual (Page 277)

8 Troubleshooting
8.2.2 Troubleshooting of Warnings
8-26
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
Display
Warning Name
Situation at Warning
Occurrence
Cause Corrective Actions
A.900
Position Error
Pulse Overflow
Wiring of the linear ser-
vomotor U, V, or W line
is incorrect.
Check the wiring of the cable for lin-
ear servomotor main circuit.
Check whether there is any loose con-
nection in linear servomotor wiring or
linear scale wiring.
The SERVOPACK gain
is too low.
Check the SERVOPACK gain.
Increase the servo gain by using the
function such as advanced autotuning.
The position reference
acceleration is too high. Lower the position reference acceler-
ation.
Apply a smoothing function, such as a
position reference acceleration/decel-
eration time constant (Pn216).
The excessive position
error alarm level
(Pn520) is too low for
the operating condi-
tions.
Check the excessive position error
alarm level (Pn520). Set an appropriate value for the
Pn520.
A SERVOPACK fault
occurred.
−
Turn the power supply OFF and then
ON again. If the alarm still occurs, the
SERVOPACK may be faulty. Replace
the SERVOPACK.
A.901
Position Error
Pulse Overflow
Alarm at Servo
ON
When the linear servo-
motor power was OFF,
the linear servomotor
moved without clearing
the counter for position
error pulses. The num-
ber of position error
pulses exceeded the
maximum number of
pulses allowed.
Check the error counter (Un008) in
servo OFF state.
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).
A.910
Overload:
Warning before
alarm A.710 or
A.720 occurs
The linear servomotor
or linear scale wiring is
incorrect or the connec-
tion is faulty.
Check the wiring.
Correct the linear servomotor and lin-
ear scale wiring if they are wrong.
The linear servomotor is
in excess of the over-
load protective charac-
teristics.
Check the overload characteristics of
the linear servomotor and reference
input.
Reconsider the load and operation
conditions.
Or, check the linear servomotor capac-
ity.
The linear servomotor is
not driven due to a
mechanical factor and
the operating load has
become excessive.
Check the reference input and motor
speed.
Improve the mechanical factor.
A SERVOPACK fault
occurred.
−
The SERVOPACK may be faulty.
Replace the SERVOPACK.
A.911 Vibration
Abnormal vibration was
detected while the linear
servomotor was mov-
ing. Check whether unusual sound is gen-
erated from the linear servomotor,
and check the speed and force wave-
form of the linear servomotor.
Lower the motor speed or the lower
the servo gain by using the function
such as one-parameter tuning.
The mass ratio (Pn103)
is larger than the actual
value or greatly
changes.
Check the mass value.
Set an appropriate value for the mass
ratio (Pn103).