Mitsubishi MELSEC-WS0-CPU0 User Manual page 89

LED indication on module
CPU module
Safety I/O module
(WS0-CPU0, WS0-
(WS0-XTIO or
CPU1 or WS0-CPU3)
WS0-XTDI)
MS =  Green All safety I/O modules:
MS =  Green
All LEDs temporarily All LEDs temporarily
off and then LED test off and then LED test
sequence. sequence.
Diagnostics
Possible error
codes
CPU module:
0x000A0011
CPU module:
0x00100011
CPU module:
0x002D4006
CPU module:
0x003E4006
Possible reasons
Function block error with dual channel
input evaluation (e.g. Emergency stop,
Magnetic switch): Discrepancy error at
pair 1 of function block:
 Cable interruption or short circuit to
0 V at one of both input signals of
the input pair.
 Hardware failure of sensor, e.g. one
of both contacts/outputs is
permanently closed (High) or
opened (Low).
 Defect sensor (one of both signals
does not change to the
corresponding state to the other
input within the configured
discrepancy time.
 Opening or closing of safety door
was too slow, so that the 2 contacts
switches (e.g. reed contacts) did not
switch within the configured
discrepancy time.
 Function block error (EDM or Valve
monitor): Feedback signal did not
follow the control signal within the
max. feedback delay time.
 Hardware failure of connected
relay/valve or failure in the wiring.
 Used relay/valve has greater
switching delay for monitor contact.
 Power supply of CPU module had
short voltage dip (to almost 0 V).
 Power supply of CPU module had a
voltage drop (approx. down to 6
V...16 V) and increased back to
operating range.
The system has performed a restart
because interferences have been
detected in the FLEXBUS+
communication:
 FLEXBUS+ communication
(backplane communication to I/O
modules and to network modules)
disturbed due to EMC disturbance.
 FLEXBUS+ communication
(backplane communication to I/O
modules and to network modules)
disturbed due to critical fault in any
safety I/O module (I/O modules or
network module). In this case this is
a follow on error and there will be
also other critical faults with almost
the same time stamp (± 1 s) in the
diagnosis history.
Chapter 10
Possible measures
 Check the wiring of the effected
input and check switching capability
of both contacts/outputs of the
connected sensor.
 Check mechanical dependency of
both switches.
 Replace switch/sensor in hardware
installation
To reset the error the effected input
pair has to change within the
configured discrepancy time from
Low/Low to High/High for equivalent
dual channel inputs, from Low/High to
High/Low for complementary dual
channel inputs.
 Increase Max. feedback delay time
of the function block, if acceptable
for the application.
 Replace relay/valve in the hardware
installation.
 Ensure that power supply is
capable to buffer power interruption
up to 20 ms.
 Ensure that power supply is
capable to drive the load, so that
switching of loads does not cause a
drop of the supply voltage.
 Check power supply wiring of CPU
module. Use separate wires to
other heavy loads to avoid voltage
drops on the supply cable by other
load currents.
 Check installation for EMC aspects
(FE connection of DIN mounting rail
and control cabinet, star wiring of
power supply (24 V and 0 V), local
separation of power parts and
control parts,...)
 Check the other diagnosis
messages with almost the same
time stamp.
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