Mitsubishi Electric QJ71MT91 User Manual page 264

11 TROUBLESHOOTING
Error
Error Name
Code
7385
H
MODBUS device
specification error
7386
H
Byte count
7390
H
specification error
Received data
7391
H
size error
Reference type
7392
H
error
7393 Data unit error
H
Online change
7394
H
error
MBAP header
7395
H
error
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Description
The range of the MODBUS
device specified in the
received request message
exceeds the maximum
value* of the MODBUS
device.
*: The maximum value of
the extended file register
is "10000", and that of
any other MODBUS
device is "65536".
The access points of the
MODBUS device specified
in the received request is
greater than the maximum
access points of the
corresponding function.
The write points of the
received request message
does not match the
specified byte count.
The write device data size of
the received request
message does not match
the specified byte count.
The reference number value
specified in the received
request message (FC: 20,
FC: 21) is incorrect.
• The contents of the data
unit in the received request
message are incorrect.
• The size of the received
request message is
smaller than the minimum
size or greater than the
maximum size required for
the relevant function code.
A write request message
was received in an online
change disable status.
The contents of the MBAP
header in the received
request message are
incorrect.
Lit LED Corrective Action
Review the specified data of
the MODBUS device on the
COM.ERR.
master side from which the
request message was sent.
Review the specified data of
the MODBUS device on the
COM.ERR.
master side from which the
request message was sent.
Review the specified data of
the write points and byte count
on the master side from which
COM.ERR.
the request message was
sent.
Review the specified data of
the write device data size and
byte count on the master side
COM.ERR.
from which the request
message was sent.
Review the specified
reference number value on the
COM.ERR.
master side from which the
request message was sent.
Review the contents of the
request message on the
COM.ERR.
master side from which the
request message was sent.
• While online change is
disabled, do not issue a write
request message.
• Turn ON b2 of the intelligent
COM.ERR.
function module switch 2
(communication condition
setting) to enable the online
change.
Review the contents of the
request message on the
COM.ERR.
master side from which the
request message was sent.
MELSEC-Q
Occurrence
1) 2) 3) 4)
(Continued on next page)
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5)