
11 Inspection, Maintenance, and Troubleshooting
11.2.3 Troubleshooting of the Servo Drive Alarms
11-32
A.F1A:
Converter AC Power
Supply Open Phase
(The voltage was low for
one second on phase L1,
L2, or L3 when the main
power supply was turned
ON.)
The three-phase power supply
wiring is faulty.
Check the power supply wiring.
Make sure the power supply wiring
is correct.
The three-phase power supply is
unbalanced.
Measure the voltage for each phase
of the three-phase power supply.
Balance the power supply by chang-
ing phases.
Power regeneration converter
failure
−
Turn the power supply OFF and
then ON again. If the alarm still
occurs, the power regeneration con-
verter may be faulty. Replace the
power regeneration converter.
A.F2A:
Converter AC Power
Supply Frequency
Error
(The deviation in the
power supply frequency
is large.)
The three-phase power supply
wiring is faulty.
Check the power supply wiring.
Make sure the power supply wiring
is correct.
The three-phase power supply is
unbalanced.
Measure the voltage for each phase
of the three-phase power supply.
Balance the power supply by chang-
ing phases.
An error occurred in the fre-
quency of the three-phase power
supply.
Measure the frequency of the three-
phase power supply.
Make sure the power supply wiring
is correct.
Power regeneration converter
failure
−
Turn the power supply OFF and
then ON again. If the alarm still
occurs, the power regeneration con-
verter may be faulty. Replace the
power regeneration converter.
A.F2B:
Converter AC Power
Supply Frequency
Detection Time
Exceeded
(The detection of the AC
power supply input fre-
quency was not com-
pleted within the set
time.)
The three-phase power supply
wiring is faulty.
Check the power supply wiring.
Make sure the power supply wiring
is correct.
The three-phase power supply is
unbalanced.
Measure the voltage for each phase
of the three-phase power supply.
Balance the power supply by chang-
ing phases.
An error occurred in the fre-
quency of the three-phase power
supply.
Measure the frequency of the three-
phase power supply.
Make sure the power supply wiring
is correct.
Power regeneration converter
failure
−
Turn the power supply OFF and
then ON again. If the alarm still
occurs, the power regeneration con-
verter may be faulty. Replace the
power regeneration converter.
A.F30:
External Dialog Box
Error
(There is an error in the
connection to the exter-
nal dynamic brake.)
There is an error in the connec-
tion to the external dynamic
brake.
Make sure that the external dynamic
brake is connected correctly.
Connect the external dynamic brake
correctly. If the alarm still occurs,
the SERVOPACK may be faulty.
Replace the SERVOPACK.
The external DB circuit failed.
−
Replace the external dynamic brake
circuit.
A parameter is not set correctly.
Check the settings of Pn001.0 and
Pn601.
Correct the settings of Pn001.0 and
Pn601.
A.F3B:
Converter AC Power
Supply Phase
Sequence Error
(An error occurred in the
AC power supply phase
sequence.)
The three-phase power supply
wiring is faulty.
Check the power supply wiring.
Make sure the power supply wiring
is correct.
The phases of the three-phase
power supply was different
before and after an instantaneous
power interruption.
−
Modify the power supply so that the
phases remain fixed.
Power regeneration converter
failure
−
Turn the power supply OFF and
then ON again. If the alarm still
occurs, the power regeneration con-
verter may be faulty. Replace the
power regeneration converter.
(cont’d)
Alarm:
Alarm Name
Cause
Investigative Actions
Corrective Actions