9 Troubleshooting and Maintenance
9-40
CJ-series DeviceNet Units Operation Manual for NJ-series CPU Unit(W497)
84740000 hex Bus Off
Detected
A Bus Off error
occurred (i.e., com-
munications
stopped because
there were too
many communica-
tions errors).
• The master and slave have dif-
ferent baud rates.
• Communications cable lengths
(trunk line and branch lines) are
unsuitable.
• A communications cable is dis-
connected or loose.
• The terminating resistance is
somewhere other than the ends
of the trunk line.
• Noise
S
page 9-55
84750000 hex Remote I/O
Communica-
tions Error
A timeout occurred
in remote I/O com-
munications.
• The master and slaves have dif-
ferent baud rates.
• Communications cable lengths
(trunk line and branch lines) are
unsuitable.
• A communications cable is dis-
connected or loose.
• The terminating resistance is
somewhere other than the ends
of the trunk line.
• Noise
SU
page 9-56
84760000 hex Remote I/O
Communica-
tions Error
(during Slave
Operation)
An error occurred in
remote I/O commu-
nications.
• The master is not in operation.
• The master and slaves have dif-
ferent baud rates.
• Communications cable lengths
(trunk line and branch lines) are
unsuitable.
• A communications cable is dis-
connected or loose.
• The terminating resistance is
somewhere other than the ends
of the trunk line.
• Noise
S
page 9-57
84770000 hex Slave COS
Send Failed
An attempt was
made to send COS
data to the master
using the Slave
COS Send Switch
(software switch 2,
device variable
*_Sw2SlavCOSSen
dCmd), but the
send failed.
• A COS connection to the mas-
ter is not open.
• A Bus Off state occurred.
• A network power error
occurred.
• A send timeout occurred.
S
page 9-58
048A0000 hex File
Read/Write
Error
An error occurred
when user setup
data was read from
an SD Memory
Card in the CPU
Unit or when data
was written as a file
to an SD Memory
Card.
• The available capacity on the
SD Memory Card was insuffi-
cient to write a file.
• Write-protection is set on the
SD Memory Card when you
write to a file.
• Noise
• The SD Memory Card is dam-
aged.
• The CPU Unit has failed.
US
page 9-58
148C0000 hex Invalid Mes-
sage Timer
List Error
The data in the
message monitor-
ing timer list is not
correct.
• The power supply was inter-
rupted while writing the mes-
sage-monitoring timer list to the
non-volatile memory.
US
page 9-59
Event code Event name Meaning Assumed cause
Level
Reference
Maj Prt Min Obs Info
To Next Page
Loading...
