A - 111
 Appendices
AC Servomotors/Servo Drives 1S-series with Built-in EtherCAT® Communications User’s Manual (I586)
A-4  Sysmac Error Status Codes
A
A-4-1  Error List
387D0000 Regeneration Over-
load Warning
The Regeneration Load 
Ratio (4150-81 hex) 
exceeded 85%.
• The regeneration process-
ing is set inappropriately
• The Regeneration Resistor 
is selected inappropriately
• The Regeneration Resistor 
is used for continuous 
regenerative braking
• The applied power supply 
voltage is higher than the 
specified value
• Regeneration Resistor fail-
ure
√ P.  A -17 2
387E0000 Motor Vibration 
Warning
The motor vibration, which 
was higher than or equal to 
the level set in the Vibra-
tion Detection - Detection 
Level (3B70-01 hex), was 
detected.
• The control parameter is set 
inappropriately
• The rigidity decreased due 
to mechanical looseness or 
wear 
√ P.  A -17 3
78220000 Command Warning A command could not be 
executed.
• The Switch ON command 
was received
• The Enable operation com-
mand was received
• An operation command in 
the prohibition direction was 
received after the immedi-
ate stop by the Drive Prohi-
bition Input or Software 
Position Limit
• Homing started
• The positioning start com-
mand was received in the 
Profile position mode
√ P.  A -17 4
84B00000 EtherCAT Communi-
cations Warning
An EtherCAT communica-
tions error occurred more 
than one time.
• An EtherCAT communica-
tions cable is disconnected, 
broken, short-circuited, or 
has a contact failure in a 
daisy chain configuration.
• In a ring topology configura-
tion, the ring disconnection 
status occurred.
• In a ring topology configura-
tion, the ring disconnection 
status was fixed.
•Noise
• Failure of the EtherCAT 
physical layer of a Servo 
Drive
√ P.  A -17 5
90A00000 Unit Restarted Restart was performed. • Restart was performed √ P.  A-1 7 5
98210000 STO Detected The safety input OFF state 
was detected via the safety 
input signal or EtherCAT 
communications.
• The cable is disconnected 
or broken
• The STO input was turned 
OFF via EtherCAT commu-
nications
√ P. A-1 76
Event code 
(hex)
Event name Description Assumed cause
Level
Refer-
ence
Min
Obs
Info