11 - 18 11 - 18
MELSEC-Q
11 TROUBLESHOOTING
11.2 Error Code Tables
The following shows the error codes, error contents, and corrective action for errors
that are generated during communication between the Q series C24 and an external
device.
The signal name in the following table indicates the CH
side LED on status or
communication error status that is stored into buffer memory address 201
H/202H when
an error occurs.
The CH
side LED on status and communication error status can be confirmed by GX
Developer's System monitor or GX Configurator-SC. (Refer to Section 11.1.1.)
For errors without a corresponding signal name entered to errors generated with the
MC protocol communication, "NAK" comes on.
11.2.1 Error code table
The following shows the error codes, error details, and corrective actions for the errors
that may occur during communication using MC protocol (excluding A compatible 1C
frame), non procedure protocol, bidirectional protocol, or pre-defined protocol.
("
" in the table is the error code when the target CPU is not a Q/QnACPU.)
Protocol
Error code
(Hexa-
decimal)
Error Description
Signal
name
Corrective action
MC
Non
Proce-
dure
Bidire-
ctional
Pre-
defined
3E8H
to
3FFF
H
⎯ (Error detected by the CPU) ⎯
• Refer to Appendix of the QCPU User's
Manual (Hardware Design,
Maintenance and Inspection) and take
corrective action.
4000H
to
4FFF
H
⎯ (Error detected by the CPU) ⎯
• Refer to Appendix of the QCPU User's
Manual (Hardware Design,
Maintenance and Inspection) and take
corrective action.
• If this error occurs during CPRTCL
instruction execution, identify the CPU
error, and correct the CPU device No.
that is specified in the Non-conversion
or Conversion variable data storage
area.
7101H
7102H
System error
• The OS of the Q series C24 detected
some error.
⎯ (
1)
7103H
Programmable
controller access
error
• Cannot communicate with the Q series
C24 CPU.
C/N
• Make the watchdog timer (timer 1) time
longer.
• Perform a self-loopback test, and check
if the CPU can communicate.
7104H
to
7116
H
System error
• The OS of the Q series C24 detected
some error.
⎯ (
1)
7140H Request data error
• Number of request points exceeds the
range for the command.
• A word device was designated in a bit
units command.
• The last device No. exceeds the range.
Given device last No. Designated head
device No. + Desi
nated number of points
PRO
• Check and correct the external device
transmit message and restart data
communications.
• If no error is found in the device range,
clear the programmable controller CPU
information and retry. (Refer to Section
11.1.7.)
7141H System error
• The OS of the Q series C24 detected
some error.
⎯ (1)
7142H Device name error
• A device that cannot be designated by
the given command was designated.
PRO
• Check and correct the external device
transmit message and restart data
communications.
• If no error is found in the device name,
clear the programmable controller CPU
information and retry. (Refer to Section
11.1.7.)