Fx 1S /Fx 1N /Fx 1Nc /Fx 2N /Fx 2Nc Plcs; Error Detection Devices - Mitsubishi Electric MELSEC-Q Structured Programming Manual

FXCPU Structured Programming Manual
[Device & Common]
5.2 FX /FX
1S 1N
5.2.1

Error detection devices

1. Error detection (M8060 and later and D8060 and later)
When some devices among M8060 to M8067 turn ON, D8004 stores the smallest device number and M8004
turns ON.
1) M8063 and M8067 are cleared when the PLC mode switches from STOP to RUN.
Note that M8068 and D8068 are not cleared.
2) When M8069 is set to ON, the PLC executes the I/O bus check. If an error is detected, D8061 stores the
error code ("6103" or "6104") and M8061 turns ON.
When D8061 stores "6104", M8009 turns ON and D8009 stores the I/O numbers in the unit where 24V
DC power failure has occurred.
Only FX
2N
3) When units and blocks having programmed I/O numbers are not actually connected, M8060 turns ON
and D8004 stores the head device number of unconnected units/blocks.
Only FX /FX
U
Example: When X020 is unconnected
1 0 2 0
2. Operations of special devices for error detection
Special auxiliary relays for error detection and special data registers for error detection operate under the
relationship shown below.
The error occurrence state can be checked by monitoring the contents of auxiliary relays and data registers
from a programming tool or by using the PLC diagnosis function.
D8009
D8060
M8069
D8061
I/O bus
check
D8063
D8064
D8065
D8066
Monitor the
contents of
D8067
D to check
the error code.
254
/FX /FX /FX
1NC 2N 2NC
/FX PLCs support this function.
2NC
PLCs support this function.
2NC
Value converted into BCD
Device number 10 to 337
1:Input X 0:Output Y
M8009 24 VDC failure
M8060 I/O configuration error
M8061 PLC hardware error
M8063 Parallel link error
M8073 Parallel link mode
M8063 RS-232C
communication error
M8064 Parameter error
M8065 Syntax error
M8066 Circuit error
M8067 Operation error
M8068 Operation error latch
5.2 FX1S/FX1N/FX1NC/FX2N/FX2NC PLCs
PLCs
D8004
Special M number
(smallest number)
of error occurrence
D8069
Clear errors, and then forcibly clear
M8068 using a programming tool.
D8068
M8004
Turns ON when
an error occurs.
Error step number
1st error step
No. latch
5 Errors