YASKAWA E-V Series User Manual page 315

9 Troubleshooting
9.2.2 Troubleshooting of Warnings
Warning
Warning Name
Display
Regenerative
Overload:
A.920
Warning before
the alarm A320
occurs
Dynamic Brake
Overload:
A921
Warning before
the alarm A.731
occurs
Change of
A.941 Parameters
Requires Restart
A.971 Undervoltage
9-22
Situation at Warning
Occurrence
The power supply volt-
age is in excess of the Measure the power supply voltage.
specified range.
The external regenera-
tive resistance, servo
amplifier capacity, or Check the operating conditions or
regenerative resistor capacity using the capacity selection
capacity is insufficient software SigmaSize+, etc.
or a continuous regener-
ative state occurs.
Regenerative power
continuously flowed
Check the load on the servomotor dur-
back because negative
ing operation.
load was continuously
applied.
The servomotor is
driven by an external Check the operating conditions.
force.
The moving energy at a Check the operating frequency of the
DB stop exceeds the DB DB with power consumed by DB
resistance capacity. resistance (Un00B).
A SERVOPACK fault
−
occurred.
Parameters that require
−
the restart have been
changed.
The power supply volt-
age for a 200 VAC
model is 120 V or
below or the power sup- Measure the power supply voltage.
ply for a 400 VAC
model is 240 V or
below.
The power supply volt-
age dropped during Measure the power supply voltage.
operation.
An instantaneous power
Measure the power supply voltage.
failure occurred.
The fuse in the SERVO-
−
PACK is burned out.
A SERVOPACK fault
−
occurred.
Cause
Set the power supply voltage within
the specified range.
Change the regenerative resistance,
regenerative resistor capacity, or SER-
VOPACK capacity. Reconsider the
operating conditions using the capac-
ity selection software SigmaSize+,
etc.
Reconsider the system including the
servo, machine, and operation condi-
tions.
Do not drive the motor with external
force.
• Reduce the servomotor reference
speed.
• Reduce the mass.
• Reduce the number of times of the
DB stop operation.
The SERVOPACK may be faulty.
Repair or replace the SERVOPACK.
Turn OFF the power and ON again.
Use a power supply voltage within the
specified range.
Increase the power supply capacity.
Set the power supply voltage to the
specified range. Lower the instanta-
neous power cut hold time (Pn509).
Repair or replace the SERVOPACK
and connect an AC/DC reactor to the
SERVOPACK.
The SERVOPACK may be faulty.
Repair or replace the SERVOPACK.
Corrective Actions