Table of Contents
11
TROUBLESHOOTING
11 TROUBLESHOOTING
11
11.1 Troubleshooting
No.
Symptom
1 RUN LED turned
off.
2 ERR. LED turned
on.
3 COM. ERR. LED
turned on.
11 - 1
This chapter explains the error details and corrective actions.
(1) Troubleshooting of errors indicated by LEDs
Check Item
Check the mounting status of the
QJ71MT91.
Check the power supply capacity.
Check the programmable controller
CPU.
Check for a watch dog timer error (X1F). • Reset the programmable controller
Check the intelligent function module
switch 1 (operation mode setting) value.
Check the intelligent function module
switch 2 (communication condition
setting) value.
Check the intelligent function module
switch 3, 4 (IP address setting) value.
Check if the QJ71MT91 is not mounted
with the A mode QCPU.
Check if the module is in the hardware
or self-loopback test mode.
Refer to "RUN LED turned off."
Check if the basic parameter setting,
error completed (X2) is on.
Check if the automatic communication
parameter setting, error completed (X5)
is on.
Corrective Action
Switch the power off and remount the
QJ71MT91.
Change the power supply module.
If the programmable controller CPU is
faulty, take corrective action according
to the QCPU User's Manual (Hardware
Design, Maintenance and Inspection).
CPU or power the programmable
controller off and then on.
• If the problem still persists after
resetting it again, the possible cause is
a hardware fault. Perform a hardware
test, and replace the QJ71MT91.
Check the setting range of each
intelligent function module switch, and
correct the value.
Mount the QJ71MT91 with the Q mode
QCPU.
• Restart the test after checking the
mounting status of the QJ71MT91.
• If the ERR. LED turns on again, the
possible cause is a hardware fault.
Change the QJ71MT91.
Refer to "Basic parameter setting, error
completed (X2) turned on."
Refer to "Automatic communication
parameter setting, error completed (X5)
turned on."
MELSEC-Q
Reference
Section
Section 6.1
Section 3.1
Section 6.6
Section 2.1
Section 6.5.1
Section 6.5.2
This section
(1)-1
This section
(2)-3
This section
(2)-5
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