12   Troubleshooting
12 - 42
NX-series EtherNet/IP Coupler Unit User’s Manual (W536)
Event name NX Unit Startup Error Event code 84C50000 hex
Meaning Starting an NX Unit failed.
Source EtherNet/IP Source details EtherNet/IP 
Coupler Unit
Detection 
timing
When power is 
turned ON to 
the EtherNet/IP 
Coupler Unit, 
the Slave Ter-
minal is 
restarted, or an 
error is reset in 
the EtherNet/IP 
Coupler Unit
Error 
attributes
Level Minor fault Recovery Cycle power to 
the EtherNet/IP 
Coupler Unit or 
restart the 
Slave Terminal.
Log category System
Effects User program Continues. Operation When Fail-soft Operation Is Set to Fail-soft
• EtherNet/IP Coupler Unit, NX Bus
I/O refreshing for all of the NX Units that have a 
startup error in the Slave Terminal stops.
Messages cannot be sent to the NX Units that 
have an initialization error in the Slave Terminal.
When Fail-soft Operation Is Set to Stop
• EtherNet/IP Coupler Unit, EtherNet/IP Communi-
cations
Ethernet communication stops.
• EtherNet/IP Coupler Unit, NX Bus
I/O refreshing for the NX Units in the Slave Termi-
nal stops.
Messages cannot be sent to the NX Units that 
have a startup error in the Slave Terminal.
Sys-
tem-defined 
variables
Variable Data type Name
None --- ---
Cause and 
correction
Assumed cause Correction Prevention
A startup error occurred in an NX 
Unit.
Cycle the power supply to the 
Communication Coupler Unit. If 
this error occurs again even after 
you cycle the power supply, 
replace the NX Unit.
None
Attached 
information
Attached information 1: Slot number of the NX Unit where the error occurred
Precautions/
Remarks
None