Error Code; Error Code Type - Mitsubishi MELSEC Q4ARCPU User Manual

6. ERROR CODE

If an error occurs when the PLC is powered ON, switched to RUN status or
running, the QnACPU module executes the self diagnostics function to display the
error (LED display, message display) and store the error information into the
special relay SM and special register SD.
Also, if an error occurs when a communication request is issued from a peripheral
device, special function module or network system, the QnACPU module returns
the error code (4000
The following explains the QnACPU errors and the corresponding corrective
actions.

6.1 Error Code Type

Errors are detected by the self diagnostics function of CPU module or during
communication with CPU module.
The following table classifies the errors according to the detection pattern,
detection location and error code.
Error detection
pattern
Detection by the self
diagnostics function of
CPU module
Detection at
communication with
CPU module
*1: CPU module error codes are classified into minor, moderate, major errors as
shown below.
• Minor error:
• Moderate error: Errors that may cause the CPU module to stop the
• Major error:
Determine the error level, i.e. whether the operation can be continued or stopped,
by referring to "Operating Statuses of CPU" described in Section 6.3 "Error Code
List"
to 4FFF ) to the request source.
H H
Error detection
Error code
location
CPU module 1000 to 10000*1
CPU module 4000
Serial
communication 7000
module, etc.
CC-Link module B000
Ethernet module C000
MELSECNET/10
F000
network module
Errors that may allow the CPU module to continue the
operation, e.g., battery error.
(Error code: 1300 to 10000)
operation, e.g., WDT error.
(Error code: 1300 to 10000)
Errors that may cause the CPU module to stop the
operation, e.g., RAM error.
(Error code: 1000 to 1299)
Section 6.3
to 4FFF Q4ARCPU User's Manual
H H
Serial Communication Module User's
to 7FFF
H H
Manual, etc.
CC-Link System Master/Local Module
to BFFF
H H
User's Manual
to CFFF Ethernet Interface Module User's Manual
H H
For QnA/Q4AR MELSECNET/10
to FFFF
H H
Network System Reference Manual
89
Reference