Mitsubishi Electric MELSEC A Series User Manual page 114

Table 6.2 Error Code List for AnACPU (Continue)
Error
Error
Code
Massage
(D9008)
"OPE 21
CIRCUIT
ERROR"
(Checked
at power
on.)
"WDT 22
ERROR"
(Checked at
execution of
END
processing.)
Detailed
Error CPU
Code States
(D9091)
211 STOP The operation circuit
for index qualification in
the CPU does not work
correctly.
212 Hardware (logic) in the
CPU does not operate
correctly.
213 The operation circuit
for sequential
processing in the CPU
does not operate
correctly.

STOP Scan time is longer
than the WDT time.
(1) Scan time of the
(2) Scan time has been
101
Error and Cause
user's program has
been extended due
to certain
conditions.
extended due to
momentary power
failure occurred
during scanning.
Corrective Action
Since this is CPU
hardware error, consult
Mitsubishi
representative.
(1) Calculate and check
the scan time of user
program and reduce
the scan time using
the CJ instruction
or the like.
(2) Monitor contents of
special register
D9005 using a
peripheral device.
If the contents are
other than 0, power
supply voltage may
not be stable.
Check power supply
and reduce variation
in voltage.