Self-Diagnostics Functions - Mitsubishi Electric MELCEC Q Series User Manual

4. CPU MODULE
4.1.4

Self-diagnostics functions

Self-diagnosis is a function that a CPU module diagnoses itself for the presence of any
abnormalities.
(1)
(2)
(3)
While turning on the programmable controller power or when an error occurs in the
programmable controller RUN, the error is detected and displayed, and the operation
is stopped by the self-diagnostics function, which the CPU module performs, to
prevent programmable controller malfunctions and give preventive maintenance.
The CPU module stores the error occurred last to a special register D9008 as an
error code, and stores further detailed error code to a special register D9091.
Even with the power-off, the latest error information and 15 errors in the past are
stored by battery backup.
With a GPP function software package for the AnUCPU, contents of up to 16 errors
can be confirmed with the peripheral devices.
Reset (All clear) in the past error information can be performed by operating "latch
clear" in the CPU module.
The following shows contents of the error information. (The error which occurred
last):
(a) The time and date of error occurrences..... Year, month, day, hour, minute,
(b) Error Code................................................. The content of the special register
(c) Detailed error code.................................... The content of the special register
(d) Error step and error module installation
address..................................................... The content of the special register
second (Clock data)
D9008
D9001
D9010, D9000, D9002
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