5.3 Troubleshooting Alarms
5
Maintenance
5-17
A.521:
Autotuning Alarm
(Vibration was
detected while
executing the
custom tuning,
Easy FFT, or the
tuning-less func-
tion.)
The Servomotor
vibrated considerably
while performing the
tuning-less function.
Check the waveform of
the motor speed.
Reduce the load so that
the moment of inertia ratio
is within the allowable
value. Or increase the
load level or reduce the
rigidity level in the tuning-
less level settings.
*1
The Servomotor
vibrated considerably
while performing cus-
tom tuning or Easy
FFT.
Check the waveform of
the motor speed.
Check the operating pro-
cedure of corresponding
function and implement
corrections.
*1
A.550:
Maximum Speed
Setting Error
The setting of Pn385
(Maximum Motor
Speed) is greater than
the maximum speed.
Check the setting of
Pn385, and the upper
limits of the maximum
motor speed setting
and the encoder output
resolution setting.
Set Pn385 to a value that
does not exceed the max-
imum motor speed.
*1
A.710:
Instantaneous
Overload
A.720:
Continuous
Overload
The wiring is not cor-
rect or there is a faulty
connection in the
motor or encoder wir-
ing.
Check the wiring.
Make sure that the Servo-
motor and encoder are
correctly wired.
*1
Operation was per-
formed that exceeded
the overload protec-
tion characteristics.
Check the motor over-
load characteristics and
Run command.
Reconsider the load and
operating conditions. Or,
increase the motor
capacity.
–
An excessive load
was applied during
operation because the
Servomotor was not
driven due to
mechanical problems.
Check the operation
reference and motor
speed.
Correct the mechanical
problem.
–
A failure occurred in
the SERVOPACK.
–
The SERVOPACK may be
faulty. Replace the SER-
VOPACK.
–
A.730 and
A.731:
Dynamic Brake
Overload
(An excessive
power consump-
tion by the
dynamic brake
was detected.)
The Servomotor was
rotated by an external
force.
Check the operation
status.
Implement measures to
ensure that the motor will
not be rotated by an
external force.
–
When the Servomo-
tor was stopped with
the dynamic brake,
the rotational or linear
kinetic energy
exceeded the capac-
ity of the dynamic
brake resistor.
Check the power con-
sumed by the DB resis-
tor to see how
frequently the DB is
being used.
Reconsider the following:
•
Reduce the Servomotor
command speed.
•
Decrease the moment
of inertia ratio or mass
ratio.
•
Reduce the frequency of
stopping with the
dynamic brake.
–
A failure occurred in
the SERVOPACK.
–
The SERVOPACK may be
faulty. Replace the SER-
VOPACK.
–
A.740:
Inrush Current
Limiting Resistor
Overload
(The main circuit
power supply
was frequently
turned ON and
OFF.)
The allowable fre-
quency of the inrush
current limiting resis-
tor was exceeded
when the main circuit
power supply was
turned ON and OFF.
–
Reduce the frequency of
turning the main circuit
power supply ON and
OFF.
–
A failure occurred in
the SERVOPACK.
–
The SERVOPACK may be
faulty. Replace the SER-
VOPACK.
–
Continued on next page.
Continued from previous page.
Alarm Number:
Alarm Name
Possible Cause
Confirmation
Correction
Reference
