Omron NJ501-1 Series User Manual page 204

5 Troubleshooting
Event name Duplicate Unit Number
Meaning The same unit number is set for more than one Special I/O Unit or more than one CPU Bus Unit.
Source PLC Function Module
Error attributes Level
Effects User program
System-defined Variable
variables
None
Cause and Assumed cause
correction
The same unit number is set for more
than one Special I/O Unit or more
than one CPU Bus Unit.
The same unit number is assigned to
a Special I/O Unit that uses more than
one unit number and another Special
I/O Unit.
Attached Attached information 1: Rack number where error was detected, 0 to 3
information
Attached information 2: Slot number where error was detected, 0 to 9
Attached information 3: Special I/O Unit: Duplicated unit number + 20 hex
Precautions/ Check the model of the Special I/O Unit. Some Special I/O Units use up to four unit numbers.
Remarks
* For details, refer to I/O Operation for Major Fault Level Controller Errors on page 5-6.
5-38
Source details
Major fault Recovery
Stops. Operation
Data type
---
Correction
Check that the same unit number is
not used for more than one Special
I/O Unit or CPU Bus Unit by checking
the rotary switches. If the same unit
number is used more than once for
the same Unit configuration, change
the unit number.
Check whether a Special I/O Unit or
CPU Bus Unit that uses more than
one unit number is included in the
configuration. If there is, check to see
if one of the unit numbers assigned to
it is used by another Special I/O Unit
or CPU Bus Unit. If it is, change the
unit number.
CPU But Unit: Duplicated unit number + 10 hex
Event code 2405 0000 hex
I/O bus master Detection
timing
Cycle the power Log category
supply.
Stops.*
Name
---
Prevention
Make sure that the same unit number
is not used for more than one Special
I/O Unit. Also, make sure that the
same unit number is not used for
more than one CPU Bus Unit.
NJ-series CPU Unit Hardware User's Manual (W500)
At power ON or
Controller reset
System