Mitsubishi MELSEC LJ71C24, User Manual

Page: 293 / 428

15 - 24 15 - 24
15 TROUBLESHOOTING
Protocol
Error code
(Hexa-
decimal)
Error
Description
Signal
name
Corrective action
MC
Non-
proce-
dural
Bi-
direc-
tional
Pre-
defined
7E42
H
Error count error,
protocol setting
data write error
•
Number of processing points exceeds
the range allowed for the command.
•
Protocol setting data were written to the
C24 that does not support the
predefined protocol function.
PRO.
•
Modify the setting of the transmit
message from the external device so
that the request will not exceed the limit
of processing points that are allowed for
one transmission and predetermined for
each MC protocol command. Then,
retry communications.
•
When using the predefined protocol
function, use a C24 that supports the
function.
7E43
H
Device error
•
A nonexistent device was designated.
•
Device that cannot be specified by the
corresponding command was
designated.
•
The head device No. is out of range.
PRO.
•
Check and correct the external device
transmit message and restart data
communications.
7E44
H
Timer 1 time-out
error
•
A response message was not returned
within the response monitoring time
(timer 1) monitoring time. C/N
•
Increase the Response monitoring time
(timer 1).
•
When accessing another station's CPU,
check if the routing parameters match.
7E46
H
System error
•
The OS of the C24 detected some
error.
⎯
( 1)
7E47
H
Continuous request
error
•
The next request was received before a
response message was returned for the
preceding request. PRO.
•
Do not send requests continuously from
the external device.
•
Adjust the Response monitoring time
(timer 1) to the timeout time set for the
external device.
7E48
H
to
7E4C
H
System error
•
The OS of the C24 detected some
error.
⎯
( 1)
7E4D
H
Error during data
transmission
•
Mode switching was executed during
data transmission.
CHn
ERR.
•
Make arrangements between the target
device and CPU module so that mode
switching is not executed during data
transmission.
7E4E
H
System error
•
The OS of the C24 detected some
error.
⎯
( 1)
7E4F
H
Device point count
error
•
Access point count is incorrect. PRO.
•
Check and correct the external device
transmit message and restart data
communications.
7E50
H
User frame No.
designation error
•
A user frame No. outside the range was
designated.
PRO.
•
Check and correct the external device
transmit message and restart data
communications.
•
Recheck the frame No.
7E51
H
Unwritten user
frame error
•
An unwritten user frame No. was
designated.
PRO.
•
Write the frame beforehand.
•
Change the frame No. and restart data
communications.
•
Recheck the frame No.
7E52
H
User frame
overwrite error
•
A written frame No. overwrite request
was issued.
PRO.
•
Change the write destination to an
unwritten frame No.
•
When overwriting, delete the given No.
beforehand.
7E53
H
User frame access
data error
•
A nonexistent command was
designated in a subcommand.
•
Byte count exceeding the number of
bytes that can be requested was
designated.
PRO.
•
Check and correct the external device
transmit message and restart data
communications.
7E54
H
Modification allowed
error
•
Flash ROM Write Enable/Protection
Status is set to Write Enable.
•
In the Switch Setting, Setting
Modifications is set to Disable.
PRO.
•
Select Protection for the Flash ROM
Write Enable/Protection Status.
•
Select Enable for the Setting
Modifications in the Switch Setting.
7E55
H
User frame data
error
•
There is an error in the user frame
variable data.
PRO.
•
Check and correct the external device
transmit message and restart data
communications.
7E56
H
System error
•
The OS of the C24 detected some
error.
⎯
( 1)