Chapter 23 Troubleshooting - Mitsubishi Electric MELSEC Q Series User Manual

CHAPTER 23
This chapter describes how to investigate the root cause of troubles in the C Controller system and corresponding
corrective actions.
When any trouble has occurred, check the following items.
(1) LED lighting state
After checking the LED lighting state indicated on the front face of the C Controller module, refer to the following
to take actions.
Page 395, Section 23.1
(2) Display state
After checking the state of the general-purpose analog RGB display, refer to the following to take actions.
Page 399, Section 23.2
(3) Error
Refer to the following to check for any error.
Page 400, Section 23.3
(4) I/O signal
Use the following methods to check if the I/O module(s), external device(s) and user program(s) are connected
with correct I/O numbers as per the design.
• Change the input (X) ON/OFF to check if read-out by the user program is allowed.
• Use the user program to change the output (Y) ON/OFF to check if the external device status changes in
conjunction with output (Y).
(5) Cabling
Check communication cables, connectors and module terminal blocks used for any looseness or disconnection,
and check the wiring is correctly arranged.
For wiring of the C Controller module main, refer to the following.
Page 125, Section 8.7
(6) Module installation status
Check that each module is securely installed to the base unit.
For the C Controller module, refer to the following.
Page 116, Section 8.2
Then, divide the trouble sources into the following categories to resolve problems in each section:
• C Controller module
• Connection cable
• Module other C Controller module
• external devices
If performing the check items and corresponding actions described in this chapter does not resolve the problem,
the hardware may be faulty. Please consult your local Mitsubishi service center or representative, explaining the
details of the problem.
394
TROUBLESHOOTING