YASKAWA UAK series User Manual page 272

11 Inspection, Maintenance, and Troubleshooting
11.2.3 Troubleshooting of the Servo Drive Alarms
Alarm:
Alarm Name
A.40C:
Abnormal Voltage in
Converter Main Circuit
(An error occurred in the
main circuit of the power
regeneration converter.)
A.410:
Undervoltage
(The DC-bus voltage
inside the SERVO-
PACK is low.)
A.41A:
Converter DC
Undervoltage
(The DC-bus voltage
inside the power regen-
eration converter is low.)
11-18
Cause
The AC voltage is unstable.
The DC bus voltage is unstable,
or an error occurred in the main
circuit in the SERVOPACK.
The DC bus voltage is unstable,
or an error occurred in the main
circuit in the power regeneration
converter.
An error occurred in the AC/DC
voltage detection circuit in the
power regeneration converter.
• For 200-VAC SERVOPACKs:
The power supply voltage was
in the range between 125 V and
170 V.
• For 400-VAC SERVOPACKs:
The power supply voltage was
in the range between 250 V and
323 V.
The power supply voltage
dropped during operation.
Occurrence of instantaneous
power interruption.
SERVOPACK failure
• For 200-VAC power regenera-
tion converter:
The power supply voltage was
in the range between 125 V and
170 V.
• For 400-VAC power regenera-
tion converter:
The power supply voltage was
in the range between 250 V and
323 V.
The wiring of the main circuit DC
bus is incorrect.
An error occurred in the main cir-
cuit of the SERVOPACK con-
nected to the converter.
Power regeneration converter
failure
Investigative Actions
Measure the AC power supply volt-
age.
Measure the DC bus power supply
voltage.
Measure the DC bus power supply
voltage.
−
Measure the power supply voltage.
Measure the power supply voltage.
Measure the power supply voltage.
−
Measure the power supply voltage.
Check the wiring.
Separate the main circuit DC bus of
the SERVOPACK.
−
(cont'd)
Corrective Actions
Improve the power supply condi-
tions.
The SERVOPACK may be faulty.
Replace the SERVOPACK.
The power regeneration converter
may be faulty. Replace the power
regeneration converter.
The power regeneration converter
may be faulty. Replace the power
regeneration converter.
Set the power supply voltage within
the specified range.
Increase the power supply capacity.
Improve the power supply condi-
tions.
The SERVOPACK may be faulty.
Replace the SERVOPACK.
Set the power supply voltage within
the specified range.
Correct the wiring of the main cir-
cuit DC bus.
Separate the SERVOPACK and
then turn ON the power supply
again. If an alarm does not occur,
the SERVOPACK may be faulty.
Replace the SERVOPACK.
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.