Mitsubishi Electric L26CPU-BT User Manual page 353

(2) Problems on device station disconnection (when the CC-Link system has been
normally operated)
Description
Check item
of problem
Programmable
B1-1 controller CPU
check
Power supply
B1-2 (for
communication)
B1-3 Cables
Unable to link
the entire
system.
B1-4 Noise
Master station
B1-5
failure
B1-6 Link stop
Check contents
Check the error code of the
programmable controller
CPU.
Does any error occur at the
programmable controller
CPU of the master station?
Check if the module can be
recognized.
Check the power supply of
Is any voltage drop
the master station and all
occurring?
device stations.
Is there any disconnection, Check if the cable between
short-circuit or faulty the master station and device
connection? station is connected properly.
Check if the transmission
cable and power wiring are
separated enough.
Is there any noise on the
transmission cable? Check if the FG is separated
from the power system GND.
Reduce the transmission
speed and then check the
occurrence frequency.
Check if the system operates
Is the master station failed? properly after replacing the
master station.
Is the data link stop
Check if the data link stop
instruction being executed
(SB0002) is turned on.
properly?
CHAPTER 15 TROUBLESHOOTING
Check procedure
Correct the error code of the
programmable controller
CPU.
Refer to MELSEC-L CPU
Module User's Manual
(Hardware Design,
Maintenance and Inspection)
Recognize the L series
master/local module
properly.
Refer to MELSEC-L CPU
Module User's Manual
(Hardware Design,
Maintenance and Inspection)
Set the supplied voltage to
within the specified range.
Connect the cable properly.
Wire the transmission cable
and power wiring as
separated as possible.
(recommended to keep a
distance of more than
100mm)
Set FG and the power
system GND apart.
Take measures against
noise.
Reduce the transmission
speed.
Fix or replace the master
station.
Disable the data link stop
(SB0002).
Do not use devices which
read SB0002 simultaneously.
Corrective action
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351