Mitsubishi QJ71MT91 User Manual

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MELSEC-Q
11 TROUBLESHOOTING
Occurrence Error
Code
Error Name Description Lit LED Corrective Action
1) 2) 3) 4) 5)
7452H
• Transmission was attempted
using the connection not
open.
• The connection used to send
data was already closed.
• Check whether the operation
status of the target device is
normal or not.
• Check the line status for an
error.
• Retry after a little while.
7453H
Connection not
open
The connection being closed
was used to send data.
COM.ERR.
Retry after a little while.
7454H
Connection
being closed
The connection not open was
used to send data.
COM.ERR.
Retry after a little while.
7455H
TCP receive
data size error
The message greater than the
TCP maximum size was
received.
COM.ERR.
• Check whether the operation
status of the target device is
normal or not.
• Check the line status for an
error.
7460H
TCP ULP time-
out error
As the TCP ULP timer timed
out, the TCP connection was
forcibly disconnected from the
local station.
COM.ERR.
• Check whether the operation
status of the target device is
normal or not.
• Check the line status for an
error.
• As the line may be busy, retry
after a little while.
• Review the TCP ULP timer
value of the basic parameter.
7461H
TCP
connection
forcibly
disconnected
The TCP connection was
disconnected forcibly from the
target device.
(This error may be ignored
when no problems arise from
this error.)
COM.ERR.
• Check whether the operation
status of the target device is
normal or not.
• Check the line status for an
error.
• As the line may be busy, retry
after a little while.
7462H
TCP
connection
forcibly
disconnected
• The TCP connection was
closed forcibly from the local
station.
• The local station uses 64 or
more TCP connections.
Hence, the TCP connection
was closed forcibly to
maintain the TCP
connections available for
simultaneous opening under
frequently opened and closed
conditions. (This error may be
ignored when no problems
arise from this error.)
COM.ERR.
• In the preferred node
specification, specify the target
device with which
communication is made
frequently.
• Decrease the number of TCP
connections used
simultaneously.
• Check whether the operation
status of the target device is
normal or not.
• Check the line status for an
error.
• As the line may be busy, retry
after a little while.
7463H
TCP protocol
error
As a TCP protocol error was
detected, the TCP connection
was closed forcibly.
COM.ERR.
• Check whether the operation
status of the target device is
normal or not.
• Check the line status for an
error.
7471H
UDP receive
data size error
The message greater than the
UDP maximum size was
received.
COM.ERR.
• Check whether the operation
status of the target device is
normal or not.
• Check the line status for an
error.
(Continued on next page)

Mitsubishi QJ71MT91 Specifications

General

Brand	Mitsubishi
Model	QJ71MT91
Category	Controller
Language	English