YASKAWA UAK series User Manual page 286

11 Inspection, Maintenance, and Troubleshooting
11.2.3 Troubleshooting of the Servo Drive Alarms
Alarm:
Alarm Name
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.)
A.F2A:
Converter AC Power
Supply Frequency
Error
(The deviation in the
power supply frequency
is large.)
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.)
A.F30:
External Dialog Box
Error
(There is an error in the
connection to the exter-
nal dynamic brake.)
A.F3B:
Converter AC Power
Supply Phase
Sequence Error
(An error occurred in the
AC power supply phase
sequence.)
11-32
Cause
The three-phase power supply
wiring is faulty.
The three-phase power supply is
unbalanced.
Power regeneration converter
failure
The three-phase power supply
wiring is faulty.
The three-phase power supply is
unbalanced.
An error occurred in the fre-
quency of the three-phase power
supply.
Power regeneration converter
failure
The three-phase power supply
wiring is faulty.
The three-phase power supply is
unbalanced.
An error occurred in the fre-
quency of the three-phase power
supply.
Power regeneration converter
failure
There is an error in the connec-
tion to the external dynamic
brake.
The external DB circuit failed.
A parameter is not set correctly.
The three-phase power supply
wiring is faulty.
The phases of the three-phase
power supply was different
before and after an instantaneous
power interruption.
Power regeneration converter
failure
Investigative Actions
Check the power supply wiring.
Measure the voltage for each phase
of the three-phase power supply.
−
Check the power supply wiring.
Measure the voltage for each phase
of the three-phase power supply.
Measure the frequency of the three-
phase power supply.
−
Check the power supply wiring.
Measure the voltage for each phase
of the three-phase power supply.
Measure the frequency of the three-
phase power supply.
−
Make sure that the external dynamic
brake is connected correctly.
−
Check the settings of Pn001.0 and
Pn601.
Check the power supply wiring.
−
−
(cont'd)
Corrective Actions
Make sure the power supply wiring
is correct.
Balance the power supply by chang-
ing phases.
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.
Make sure the power supply wiring
is correct.
Balance the power supply by chang-
ing phases.
Make sure the power supply wiring
is correct.
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.
Make sure the power supply wiring
is correct.
Balance the power supply by chang-
ing phases.
Make sure the power supply wiring
is correct.
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.
Connect the external dynamic brake
correctly. If the alarm still occurs,
the SERVOPACK may be faulty.
Replace the SERVOPACK.
Replace the external dynamic brake
circuit.
Correct the settings of Pn001.0 and
Pn601.
Make sure the power supply wiring
is correct.
Modify the power supply so that the
phases remain fixed.
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.