Mitsubishi QJ71MT91 User Manual page 234

11 TROUBLESHOOTING
No. Symptom
1 Dedicated Check if the dedicated instruction is
instruction is not active.
executed.
Check whether the programmable
(Complete device
controller CPU is in the RUN status or
(D2) does not turn
not.
on.)
While the dedicated instruction is
executed, the related starting contact
was turned on. (When a starting contact
is turned on with the related dedicated
instruction being executed, the start
instruction is ignored.)
Check whether more than the
executable dedicated instructions (8
instructions) were started.
Check whether the dedicated instruction
failed or not.
Check whether the module is waiting for
a response from the target device with
the dedicated instruction already being
executed.
2 Dedicated Check if the INIT. LED is on.
instruction failed.
Confirm the error code or exception
code stored in the control data of the
dedicated instruction.
Check whether the target device
supports the corresponding function
code.
When the MBREQ dedicated instruction
is used, check the created request
message.
Refer to "Communication with target device cannot be made if each parameter
setting is completed.".
11 - 5
(3) Troubleshooting for other symptoms
Check Item Corrective Action
Start the dedicated instruction.
RUN the programmable controller CPU.
Retry after the dedicated instruction is
completed.
Retry after the dedicated instructions
being executed are completed.
Refer to "Dedicated instruction failed.".
• Wait for the response monitoring timer
to expire.
• Check the target device status.
• If an error occurs, refer to "Dedicated
instruction failed.".
Refer to "INIT. LED does not turn on.".
Take the corresponding corrective action
and retry.
<MBRW instruction>
Change the device type of the control
data so that the function code supported
by the target device is issued.
<MBREQ instruction>
Change the send data so that the
function code supported by the target
device is issued.
Correct the request message and retry.
MELSEC-Q
Reference
Section
Chapter 10
This section
(3)-2
Section 7.2
This section
(3)-2
This section
(1)-4
Chapter 10
Section 11.3
Section 10.2
Section 10.3
Chapter 4
Section 10.3
This section
(3)-6
11 - 5