939
FX
3G
/FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
38 Error Check Method and Error Code List
38.3 Supplementary Explanation of Devices for Error Detection
31
FN
C
275-
FN
C
279
Da
ta
Transf
er 3
32
FN
C
280-
FN
C
289
H
igh Speed
Pr
ocessing 2
33
FN
C
29
0-F
N
C
299
Ext
ens
ion Fi
le
R
egi
ster
34
FN
C
300-
FN
C
305
FX
3U
-C
F-A
D
P
35
SFC•S
TL
Pr
ogr
am
m
ing
36
In
ter
rupt
Functi
on
37
Special D
evice
38
E
rro
r C
ode
A
Ve
rs
ion U
p
In
fo
rm
atio
n
B
Execution T
im
es
38.3.2 Operations of special devices for error detection
Special auxiliary relays for error detection and special data registers for error detection operate in the
relationship shown below.
The state of error occurrence can be checked by monitoring the contents of auxiliary relays and data registers
or by using the PLC diagnosis function programming tool.
38.3.3 Error detection timing
Error item
ERROR LED
status
PLC
status
Error detection timing
When power
is turned from
OFF to ON
When PLC mode
switches from
STOP to RUN
Other timing
M8060 I/O configuration error
Unlit
RUN
Check
Check
⎯
M8061 PLC hardware error
Lit
STOP
Check
⎯
Always
M8062 Serial communication error 0 [ch 0]
Unlit
RUN
⎯
⎯
When receiving signal
from counterpart station
M8063 Serial communication error 1 [ch 1]
Unlit
RUN
⎯
⎯
When receiving signal
from counterpart station
M8438 Serial communication error 2 [ch 2]
Unlit
RUN
⎯
⎯
When receiving signal
from counterpart station
M8064 Parameter error
Flickering
STOP
Check
Check
When program is changed
(STOP)
When program is
transferred (STOP)
M8065 Syntax error
Flickering
STOP
M8066 Circuit error
Flickering
STOP
M8067 Operation error
Unlit
RUN
⎯
⎯
RUN mode
M8068 Operation error latch
Unlit
RUN
M8109 I/O refresh error
Unlit
RUN
⎯
⎯
Always
M8316 Unconnected I/O designation error
Unlit
RUN
⎯
⎯
RUN mode
M8318 BFM initialization failure
Unlit
RUN
⎯
Check
⎯
M8449 Special block error
Unlit
RUN
⎯
⎯
Always
M8069
I/O
bus check
By using the PLC diagnosis function provided in the programming tool (GX Developer), Graphic
Operation Terminal (GOT 1000) or the display module (FX
3U
-7DM), the contents of the error code
(D8060 to D8067, D8438, D8449) can be checked in message format.
ON when an error
occurs
Special M number
(smallest device
number) of error
occurrence
After clearing errors, forcibly clear M8068 using the device monitor function in a programming tool.
D8009 M8009 24V DC down
D8060 M8060 I/O configuration error
D8061 M8061 PLC hardware error
D8063 M8063 Serial communication error 1
D8438 M8438 Serial communication error 2
D8064 M8064 Parameter error
D8065 M8065 Syntax error
D8066 M8066 Circuit error
D8067 M8067 Operation error
M8068 Operation error latch
D8004
M8004
D8313
32K Error step number
The error step number is also stored in
D8069, but only for programs 32K
steps and less.
1st error step latched
The error step number is also stored in
D8068, but only for programs 32K
steps and less.
D8317
M8316 Unconnected I/O
designation error
D8316
D8314
D8315
D8312
Error step number
D8449 M8449 Special block error
M8318 BFM initialization failure
D8318
D8319
Error unit number
Error BFM number
D8062 M8062 Serial communication error 0