Table of Contents
11
TROUBLESHOOTING
No.
Symptom
8 Automatic
communication
operation status
(X6) turned off.
9 Automatic
communication
error status (X7)
turned on.
10 COM. ERR. LED
status (X1B)
turned on.
11 MODBUS device
assignment
parameter setting
existence (XA)
does not turn on.
11 - 4
Check Item
Check the automatic communication
stop request.
Check whether the basic parameters
were re-set while the automatic
communication function was active.
(The automatic communication is
stopped when the basic parameters are
re-set.)
Check if the communication with the
target device is possible.
Check if dedicated instructions are
executed to the same target device
simultaneously.
Refer to "COM. ERR. LED turned on.".
Check whether the slave function is
used or not?
Check if the MODBUS device
assignment parameter setting has been
completed.
Check if the MODBUS device
assignment parameter setting, error
completed (X9) is on.
Corrective Action
Restart the automatic communication
function.
Restart the automatic communication
function after completing basic
parameter re-setting.
Check the Automatic communication
operation status storage area (0C20
0C23
) in the buffer memory and
H
identify the parameter number of the
error cause.
Take corrective actions according to the
error code currently stored in the
Automatic communication error code
storage area (0C28
to 0C67
H
exception code sent from the target
slave.
Set the execution type in the control
data of the dedicated instruction to "1:
TCP connection is closed after
instruction completion.", and execute
the automatic communication function
after the dedicated instruction is
completed.
When dedicated instructions and the
automatic communication function are
executed simultaneously, change the
settings of the target device and
change the number of TCP connections
to 2 to be connected to the QJ71MT91.
When the slave function is not used, the
MODBUS device assignment parameter
setting existence (XA) may be off.
Set the MODBUS device assignment
parameters from GX Configurator-MB or
from the sequence program.
In the setting of intelligent function
module switch 2 (communication
condition setting) - b1: MODBUS device
assignment parameter starting method,
select "OFF: Start with the default
parameters".
Refer to "MODBUS device assignment
parameter setting, error completed (X9)
turned on.".
MELSEC-Q
Reference
Section
Section 7.3
Section 5.2.1
Section 7.2
Section 7.3
Section 5.2.1
to
H
Section 11.3.1
) or the
H
Section 10.2
Section 10.3
This section
(1)-3
Section 7.4
Section 9.1.3
Section 6.6
This section
(2)-6
11 - 4
Table of Contents
