YASKAWA JUSP-MD D01A Series User Manual page 312

Warning Num-
ber: Warning
Cause
Name (Warning
Description)
Abnormal vibration was
detected at the motor
speed.
A.911:
The moment of inertia
Vibration
ratio (Pn103) value is
greater than the actual
value or is greatly
changed.
The power supply volt-
age exceeds the speci-
fied limit.
Insufficient regenera-
tive resistance, regener-
A.920: ative resistor capacity,
Regenerative SERVOPACK capacity,
Overload or converter capacity.
(Warning before Or, regenerative power
the alarm A.320 has been continuously
occurs) flowing back.
Regenerative power
continuously flowed
back because negative
load was continuously
applied.
The servomotor rotates
because of external
force.
A.921:
Dynamic Brake
The rotating energy at a
Overload
DB stop exceeds the DB
(Warning before
resistance capacity.
the alarm A.731
occurs)
A fault occurred in the
SERVOPACK or con-
verter.
A.930: The battery connection
Absolute is incorrect.
Encoder Battery
The battery voltage is
Error
lower than the specified
(The absolute
value 2.7 V.
encoder battery
voltage is lower
than the specified
A fault occurred in the
value.)
multi-winding drive
∗ Only when an
unit.
absolute encoder
is connected.
A.941:
Parameters that require
Change of
the restart have been
Parameters
changed.
Requires Restart
Investigative Actions
Check for abnormal noise from the
servomotor, and check the speed and
torque waveforms during operation.
Check the moment of inertia ratio.
Measure the power supply voltage.
Check the operating condition or the
capacity using the capacity selection
Software SigmaJunmaSize+, etc.
Check the load to the servomotor
during operation.
Check the operation status.
Check the power consumed by DB
resistance (Un00B) to see how many
times the DB has been used.
−
Check the battery connection.
Measure the battery voltage.
−
−
9.2 Warning Displays
(cont'd)
Corrective Actions
Reduce the motor speed or reduce the
servo gain by using the function such
as one-parameter tuning.
Set the moment of inertia ratio
(Pn103) to an appropriate value.
Set the power supply voltage within
the specified range.
Change the regenerative resistance,
regenerative resistor capacity, SER-
VOPACK capacity, or converter
capacity. Reconsider the operating
conditions using the capacity selection
software SigmaJunmaSize+, etc.
Reconsider the system including servo
drives, machine, and operating condi-
tions.
Take measures to ensure the servomo-
tor will not rotate because of external
force.
Reconsider the following:
• Reduce the motor reference speed.
• Reduce the moment of inertia ratio.
• Reduce the number of times of the
DB stop operation.
The SERVOPACK or converter may
be faulty. Replace the SERVOPACK
or converter.
Reconnect the battery.
Replace the battery.
The multi-winding drive unit may be
faulty. Replace the multi-winding
drive unit.
Turn the control power supply OFF
and ON again.
9
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