1-11
1 Overview of Errors
NJ-series Troubleshooting Manual (W503)
1-3 Non-fatal Errors
1
1-3-1 Types of Non-fatal Errors
Relationship between Event Codes and Error Codes
In addition to the event codes that indicate errors, the function modules and Units have their own
error codes. If there are corresponding event and error codes, you can tell what the other code is if
you know either one of them. This allows you to know when the same error is being given when you
check errors with more than one method.
The following table shows the relationship between the error codes and event codes.
* The following are system-defined variables for motion control:
First digit of the
code (hex)
Classification Meaning
0 Hardware errors An error caused by a hardware problem such as an inter-
nal part malfunction, contact failure, temperature error,
undervoltage, overvoltage, or overcurrent.
1 Data errors An error caused by incorrectly saved data or data cor-
ruption in the Controller.
2 Hardware setting errors An error caused by incorrect handling of hardware set-
tings (e.g., hardware switches) or restrictions (e.g., Unit
assignment locations).
3 Configuration errors An error caused by incorrect parameter values, parame-
ters and hardware configurations that do not match, or
configurations set by the user.
4 Software errors An error caused by Controller software.
5 User software errors An error that is caused by the user program. (For exam-
ple, an input value to an instruction that is out of range.)
6 Observation errors An error that was detected in monitoring operation that
occurs due to user settings in the Controller. (For exam-
ple, if the task period is exceeded or if a position outside
of the motion range is detected.)
7 Control errors An error caused by a control process. (For example, if
the operating status does not meet the required condi-
tions or if the timing is incorrect.)
8 Communications errors An error caused by communications with an external
device or host system.
9 Information Events that are classified as information and provide
information that do not indicate errors.
Error code (4-digit hexadecimal)
Corresponding event code
(8-digit hexadecimal)
Example: Event
code for an error
code of A123 hex
Classification Used in Upper 4 digits Lower 4 digits
Error codes in the
Motion Control
Function Module
• ErrorID output
variable for motion
control instruc-
tions
• System-defined
variables for
motion control*
Error code 0000 hex A1230000 hex
Error codes for basic
instructions
ErrorID output vari-
able for basic
instructions
5401 hex Error code 5401A123 hex
Error codes in CJ-
series Special Units
Error logs from CJ-
series Special Units
0000 hex Error code 0000A123 hex
Variable Name
_MC_COM.PFaultLvl.Code MC Common Partial Fault Code
_MC_COM.MFaultLvl.Code MC Common Minor Fault Code
_MC_COM.Obsr.Code MC Common Observation Code
_MC_AX[0..63].MFaultLvl.Code Axis Minor Fault Code