7. ERROR DISPLAY AND HANDLING WITH LADDER MONITORING
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MELSEC
GOT
Chapter7 Error display and handling with ladder monitoring
The following chart shows the error messages that are displayed during the ladder
monitor operation and the method of handling them.
Error Message Description Method of Handling
ENTRY CODE
MISMATCH
The specified keyword is
different from the keyword
that is registered in the
object PLC CPU.
Check the keyword that is
registered in the object PLC
CPU and specify again.
FILE NOT FOUND
(1) An attempt was made to
switch to the ladder
monitor screen when a
sequence program had
not been read.
(2) When the file is selected
and the
Read
key is
pressed, the selected
file does not exist in the
PLC drive.
Read the sequence
program that is written in
the object PLC CPU.
(Ex.) A sub-sequence
program can only be
specified as A3
CPU/A4UCPU.
PLC
COMMUNICATION
ERROR
(1) Cannot communicate
with PLC CPU of the
specified network No. or
station No.
(2) The specified drive does
not exist.
Check and correct the
following:
(1) Does the specified PLC
CPU exist?
(2) Is it online? (Data
communication status?)
(3) Has an error occurred?
LOCK ON OTHER
MACHINE.
PLEASE CANSEL
File is locked with the
peripheral equipment
(GPPW, GPPQ).
After reading and writing
with the peripheral
equipment (GPPW, GPPQ),
read the file again.
NOT EXISTING DRIVE,
DRIVE ERROR
(1) The specified drive does
not exist.
(2) The specified drive is
faulty.
(1) Check whether the
specified drive exists or
not.
(2) Check whether the
specified drive is faulty
or not.
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