Troubleshooting; Verifying Errors From Led Status - Mitsubishi Electric CC-Link User Manual

6 TROUBLESHOOTING

6 TROUBLESHOOTING

6.1 Verifying Errors from LED Status

The following table lists causes and corrective actions for errors indicated by LEDs on
the CC-Link embedded I/O adapter when the SW, M/S and PRM LEDs are all off (i.e.
the master module is set properly) in the system configuration example shown below.
CPU
LED status
Master CC-Link embedded I/O adapter
module
A B
PW PW
L RUN L RUN
L ERR L ERR
PW PW
L RUN L RUN
L ERR L ERR
PW PW
L RUN L RUN
L ERR L ERR
PW PW
TIME L RUN L RUN
LINE L ERR L ERR
or
TIME
LINE
PW PW
L RUN L RUN
L ERR L ERR
PW PW
L RUN L RUN
L ERR L ERR
PW PW
L RUN L RUN
L ERR L ERR
6 - 1
Master
module
Station number 1
CC-Link embedded
I/O adapter A
Cause
C
PW
L RUN Normal
L ERR
PW Since the LEDs on the CC-Link
L RUN embedded I/O adapter A are all off, the
L ERR 24 V power is not supplied or voltage is
low.
PW The CC-Link embedded I/O adapter A
L RUN is malfunctioning and the LEDs are
L ERR unstable (all lights are off, in many
cases).
PW The L RUN lights on the CC-Link
L RUN embedded I/O adapter B and beyond
L ERR are off, indicating the transmission cable
between the CC-Link embedded I/O
adapter A and B has been disconnected
or removed from the terminal block.
PW The transmission cable is shorted.
L RUN
L ERR
PW The transmission cable is wired
L RUN incorrectly.
L ERR
The transmission patterns have been
connected incorrectly.
PW The L RUN lights on the CC-Link
L RUN embedded I/O adapters A and C are off,
L ERR indicating the station numbers for A and
C are overlapping.
MELSEC-A
Station number 2 Station number 3
CC-Link embedded CC-Link embedded
I/O adapter B I/O adapter C
Corrective action
—
Check the voltage of the 24 V power supply,
and supply the proper power to the CC-Link
embedded I/O adapter.
Exchange the CC-Link embedded I/O adapter.
Identify the disconnected point by referring to
the LED status, and correct it.
Find the shorted cable among the three
transmission cables and repair it.
Check the wiring on the terminal block of the
user board and correct the incorrect wiring.
Check the transmission patterns on the user
board and correct the incorrectly connected
portions.
Restart the power supply after the overlapped
station numbers for the CC-Link embedded I/O
adapters are corrected.
: lit, : unlit, : flashing,
6
: lit, flashing or unlit
6 - 1