Appendices
A - 128
AC Servomotors/Servo Drives 1S-series with Built-in EtherCAT® Communications User’s Manual (I586)
Event name Encoder Communications Disconnection Error Event code 084A0000 hex
Description The communications disconnection was detected between the encoder and the Servo Drive.
Source
EtherCAT Master Function Mod-
ule
Source details
Slave
Detection 
timing
Continuously
Error 
attributes
Level
Minor fault
Recovery
Error reset 
(after cycling 
slave power)
Log category
System log
Effects User program Continues. Operation Power drive circuit is OFF
Indicators
EtherCAT NET RUN EtherCAT NET ERR EtherCAT LINK/ACT
--- --- ---
System
-defined 
variables
Variable Data type Name
None None None
Cause and
correction
Assumed cause Correction Prevention
Noise into the encoder cable  • Separate the motor cable and 
the encoder cable if they are 
bundled together.
• Connect the shield to FG.
• Check that the motor ground 
wire is connected to FG.
• Separate the motor cable and 
the encoder cable if they are 
bundled together.
• Connect the shield to FG.
• Check that the motor ground 
wire is connected to FG.
Contact failure of the signal line, 
and disconnection of the encoder 
Replace the encoder cable if it is 
broken. Firmly connect the 
encoder connector to the Servo 
Drive.
Confirm that the encoder is not 
broken before use, and connect 
the encoder connector to the 
Servo Drive securely.
Power supply undervoltage to the 
encoder
Use the recommended encoder 
cable.
Use the recommended encoder 
cable.
Encoder failure If this event occurs again after you 
performed all corrections shown 
above, replace the motor.
None
Attached 
information
None
Precautions/
Remarks
AL status code: -, Error No.: 2100 hex