Omron NJ501-1400 User Manual page 226

5 Troubleshooting
Errors Related to CJ-series Unit Configuration
Event name I/O Bus Check Error
Meaning An error occurred in a bus line transmission between the CPU Unit and the Units in the rack slots. Or, detection of all
Special I/O Units and CPU Bus Units was not completed when the power supply to the Controller was turned ON.
Source PLC Function Module
Error attributes Level
Effects User program
System-defined Variable
variables
None
Cause and Assumed cause
correction
The I/O Connecting Cable is discon-
nected or wires inside it are broken.
Conductive material has gotten
inside.
The connector contact is faulty due to
foreign material in the connector.
Noise
• There is data corruption in bus sig-
nals.
• There is malfunctioning in bus inter-
face circuits.
A Unit has failed.
• CPU Unit
• Special I/O Unit
• CPU Bus Unit
• I/O Connecting Cable
Attached None
information
Precautions/ None
Remarks
* For details, refer to I/O Operation for Major Fault Level Controller Errors on page 5-6.
5-46
Source details
Major fault Recovery
Stops. Operation
Data type
---
Correction
Make sure that the I/O cable connec-
tor is mated properly and then recon-
nect the connector. If the I/O cable is
broken, replace it.
If there is conductive material nearby,
blow out the Units with air.
If foreign material is stuck to the con-
nector, take off the connector and
remove the foreign material.
If the error did not result from the
above causes, cycle the power to the
Controller and see if that clears the
error. If the error occurs frequently,
check the FG, power supply lines, I/O
Connecting Cables, and other noise
entry paths, and implement noise
countermeasures as required.
If the error did not result from the
above causes, and cycling the power
to the Controller or resetting the Con-
troller does not clear the error,
replace the attached Unit or the CPU
Unit.
Event code 04010000 hex
I/O bus master Detection
timing
Cycle the power Log category
supply.
Stops.*
Name
---
Prevention
Make sure the cable is mated prop-
erly during operation. Check for vibra-
tion and shock.
Do not do any metal working in the
vicinity of the control panel. Use the
control panel only when it is closed.
Make sure that the operating environ-
ment is free of dirt and dust.
Implement noise countermeasures.
Perform regular inspections.
NJ-series CPU Unit Hardware User's Manual (W500)
Continuously
System