Error Log Functions; Error Log Table - Omron CJ1W-DRM21 Operation Manual

9 Troubleshooting and Maintenance
9-2

Error Log Functions

Errors detected by the DeviceNet Unit are stored in the error log along with the date and time of their
occurrence. You can monitor the error log by using the CX-Integrator.
Refer to the CX-Integrator Operation Manual (Cat. No. W464) for error log monitoring operations.
9-2-1

Error Log Table

Error Log Table

Each time an error occurs, one error record is recorded in the DeviceNet Unit's RAM error log table.
You can record a maximum of 96 records with Unit Ver. 1.1 or later, and a maximum of 64 records
with versions before Ver.1.1. If another error occurs when the table is full, the oldest record will be
erased to make room for the new error record.
The error log table records the following information.
• Error code (Refer to 9-2-2 Error Codes and Detail Codes)
• Detail code (Refer to 9-2-2 Error Codes and Detail Codes)
• Time of occurrence (The CPU Unit's time is used for the time stamp.)
Error Log Storage Area
When an error is detected, information on the error and the time stamp are stored in the Unit's inter-
nal RAM as an error log record. Serious errors are recorded in EEPROM as well as RAM*. The error
log records in EEPROM are retained even when Controller is turned OFF or the Unit is restarted.
The error log records in EEPROM are copied to RAM when the DeviceNet Unit is turned ON.
When the error log is read from the CX-Integrator, only the error log records in RAM are read. When
the error log is cleared from the CX-Integrator, the error log records in RAM and EEPROM are
erased.
* Refer to 9-2-2 Error Codes and Detail Codes for a table listing the error codes.
Reading and Clearing the Error Log
When you use the CX-Integrator, you can monitor the error log with the master error history read
operation. With the CX-Integrator, the error log can only be monitored and cannot be saved.
Additional Information
The CPU Unit's time information is used for the time stamps in the DeviceNet Unit's error log
records. If the time information cannot be read from the CPU Unit, the time stamp will contain all
zeroes.
Moreover, if the battery is replaced in an NJ-series controller, the time of the CPU Unit's built-in
clock must be set again the next time that power is turned ON. If the built-in clock time is not set,
the correct time information will not be recorded. If this error log is read from the CPU Unit, the
time information will not be consistent.
9-28 CJ-series DeviceNet Units Operation Manual for NJ-series CPU Unit(W497)