YASKAWA SGMJV - Page 354

10 Troubleshooting
10.2.2 Troubleshooting of Warnings
10-22
A.911 Vibration
Unusual vibration was
detected while the
motor was rotating.
Check whether unusual sound is gen-
erated from the motor, and check the
speed, and torque waveform of the
motor.
Lower the motor rotation speed or
lower the servo gain by using the
function such as one-parameter tun-
ing.
The moment of inertia
ratio (Pn103) is larger
than the actual value or
greatly changes.
Check the moment of inertia ratio.
Set an appropriate value for the
moment of inertia (Pn103).
A.920
Regenerative
Overload:
Warning before
the alarm A320
occurs
The power supply volt-
age is in excess of the
specified range.
Measure the power supply voltage.
Set the power supply voltage within
the specified range.
The external regenera-
tive resistance, servo
amplifier capacity, or
regenerative resistor
capacity is insufficient
or a continuous regener-
ative state occurs.
Check the operating conditions or
capacity using the capacity selection
software SigmaJunmaSize+, etc.
Change the regenerative resistance,
regenerative resistor capacity, or SER-
VOPACK capacity. Reconsider the
operating conditions using the capac-
ity selection software SigmaJunma-
Size+, etc.
Regenerative power
continuously flowed
back because negative
load was continuously
applied.
Check the load on the servomotor dur-
ing operation.
Reconsider the system including the
servo, machine, and operation condi-
tions.
A921
Dynamic Brake
Overload:
Warning before
the alarm A.731
occurs
The servomotor is
driven by an external
force.
Check the operating conditions.
Do not drive the motor with external
force.
The rotating energy at a
DB stop exceeds the DB
resistance capacity.
Check the operating frequency of the
DB with power consumed by DB
resistance monitor (Un00B).
• Reduce the servomotor reference
speed.
• Reduce the moment of inertia.
• Reduce the number of times of the
DB stop operation.
A SERVOPACK fault
occurred.
−
The SERVOPACK may be faulty.
Replace the SERVOPACK.
A.930
Absolute
Encoder Battery
Error
(The absolute
encoder battery
voltage is lower
than the specified
value.)
(Only when an
absolute encoder
is connected.)
The battery connection
is incorrect.
Check the battery connection. Reconnect the battery.
The battery voltage is
lower than the specified
value 2.7 V.
Measure the battery voltage. Replace the battery.
A SERVOPACK fault
occurred.
−
The SERVOPACK may be faulty.
Replace the SERVOPACK.
A.941
Change of
Parameters
Requires Restart
Parameters that require
the restart have been
changed.
− Turn OFF the power and ON again.
Warning
Display
Warning Name
Situation at Warning
Occurrence
Cause Corrective Actions