11 - 17 11 - 17
MELSEC-Q
11 TROUBLESHOOTING
(d) Error log (error log 1 to 32)
• The error log area stores the 32 latest errors.
• The error log area stores the errors in order of occurrence, starting from
the error log 1.
• If 33 or more errors have occurred, the error logs are overwritten, starting
from the area of the error log 1.
Function
Master function
Contents
Automatic
communication
Dedicated instruction
Slave function
GX Developer
connection
Others
Error code
Stores a code corresponding to the error occurred at any timing such as during processing of a
request message from the master, at power-on or when changing a MODBUS
R
device
assignment parameter.
Refer to Section 11.3.3 for the error codes.
Exception code
Stores an exception code returned from a
slave in reply to a request sent by the
automatic communication function or
dedicated instruction.
When an error occurs
for a request from the
master, stores an
exception code returned
to the master.
Stores “0”.
Function code
Stores the function code with which the error originated.
Stores “0”.
Local station port No.
Stores the local station port No. at error occurrence.
Stores “0” for an error occurred below the TCP/UDP level, at power-on or in parameter setting.
Target IP address
Stores an IP address of the target station at error occurrence.
Stores “0” for an error occurred below the IP level, at power-on or in parameter setting.
Target device port No.
Stores the port No. of the target station at error occurrence.
Stores “0” for an error occurred below the TCP/UDP level, at power-on or in parameter setting.
