9.1  Alarm Displays
9-9
A.300:
Regeneration Error
An external regenerative resistor 
unit is not connected.
Check the external regenerative 
resistor unit connection.
Connect the external regenerative 
resistor unit.
The regenerative resistor unit is 
incorrectly wired, or is removed 
or disconnected.
Check the regenerative resistor unit 
connection.
Correctly connect the regenerative 
resistor unit.
The connection of the I/O signals 
(CN901) between the SERVO-
PACK and converter is faulty.
Check the connection of CN901. Correctly connect CN901.
A fault occurred in the SERVO-
PACK or converter.
−
While the main circuit power sup-
ply is OFF, turn the control power 
supply OFF and then ON again. If 
the alarm still occurs, the SERVO-
PACK or converter may be faulty. 
Replace the SERVOPACK or con-
verter.
A.320:
Regenerative 
Overload
The power supply voltage 
exceeds the specified limit.
Measure the power supply voltage.
Set the power supply voltage within 
the specified range.
Insufficient regenerative resis-
tance, regenerative resistor 
capacity. 
Or, regenerative power has been 
continuously flowing back.
Check the operating condition or 
the capacity using the capacity 
selection Software SigmaJunma-
Size+, etc.
Change the regenerative resistance, 
regenerative resistor capacity. 
Reconsider the operating conditions 
using the capacity selection soft-
ware SigmaJunmaSize+, etc.
Regenerative power continu-
ously flowed back because nega-
tive load was continuously 
applied.
Check the load applied to the servo-
motor during operation.
Reconsider the system including 
servo, machine, and operating con-
ditions.
The setting of parameter Pn600 is 
smaller than the regenerative 
resistor's capacity.
Check the regenerative resistor unit 
connection and the value of the 
Pn600.
Set the Pn600 to a correct value.
The regenerative resistance is too 
high.
Check the regenerative resistance.
Change the regenerative resistance 
to a correct value or use an external 
regenerative resistor of appropriate 
capacity.
The connection of the I/O signals 
(CN901) between the SERVO-
PACK and converter is faulty.
Check the connection of CN901. Correctly connect CN901.
A fault occurred in the SERVO-
PACK or converter.
−
The SERVOPACK or converter 
may be faulty. Replace the SERVO-
PACK or converter.
A.330:
Main Circuit Power 
Supply Wiring Error
(Detected when the 
power to the main circuit 
is turned ON.)
The regenerative resistor unit was 
disconnected when the power 
supply voltage to the SERVO-
PACK and converter was high.
Measure the resistance of the regen-
erative resistor unit using a measur-
ing instrument.
Replace the regenerative resistor 
unit.
DC power was supplied.
Check the power supply to see if it 
is a AC power supply.
Use an AC power supply.
An regenerative resistor unit is 
not connected.
Check the regenerative resistor unit 
connection.
Connect the regenerative resistor 
unit.
The  1 and  2 terminals of the 
converter are open.
Check the  1 and  2 terminals on 
the converter.
Correctly connect the  1 and  2 
terminals on the converter.
The connection of the I/O signals 
(CN901) between the SERVO-
PACK and converter is faulty.
Check the connection of CN901. Correctly connect CN901.
A fault occurred in the SERVO-
PACK or converter.
−
The SERVOPACK or converter 
may be faulty. Replace the SERVO-
PACK or converter.
(cont’d)
Alarm Number:
Alarm Name
(Alarm Description)
Cause Investigative Actions Corrective Actions