12   Troubleshooting
12 - 16
AC Servomotors/Servo Drives 1S-series with Built-in EtherCAT® Communications User’s Manual (I586)
When an error or warning occurs, the error number is displayed on the 7-segment LED display the front 
of the Servo Drive.
 
12-5-1 Troubleshooting Using Error Displays
Error List
Error No.
Name Cause Measures
Main 
(hex)
Sub 
(hex)
12 00 Overvoltage 
Error
The main circuit power 
supply voltage (P-N 
voltage) exceeded the 
operation guarantee 
range.
The P-N voltage 
exceeded the specified 
value.
Input the correct voltage.
The input voltage 
increased.
Use appropriately external devices 
such as UPS.
The Regeneration 
Resistor wiring is bro-
ken.
If a resistance value of the external 
resistor is infinite between the ter-
minal B1 and B2 of the Servo Drive, 
the wiring is broken. Replace the 
external resistor.
The External Regenera-
tion Resistor is set or 
selected inappropriately.
Confirm the necessary regeneration 
processing capacity, and connect 
an appropriate External Regenera-
tion Resistor. Also, set the parame-
ters of the External Regeneration 
Resistor to the resistance value of 
the External Regeneration Resistor 
in use.
P-N voltage increased 
because a noise of a 
Servo Drive during 
Servo ON interrupted to 
a Servo Drive during 
Servo OFF.
When several Servo Drives are 
used, DO NOT bundle motor power 
cables.
Wire so that inductance of the 
power supply cable is smaller.
You can find effect of improvement 
once a noise filter is set to the 
power line. Use one noise filter for 
each Servo Drive.
You can find effect of improvement 
once an External Regeneration 
Resistor is set to a Servo Drive with 
non built-in a Regeneration Resis-
tor.
Servo Drive failure If this event occurs again after you 
performed all corrections shown 
above, replace the Servo Drive.