Mitsubishi A2USCPU(S1), User Manual

Page: 68 / 272

4 - 15
CPU MODULE 4.
(4) When the self-diagnostics detects an error, the module will be in one of the two
modes below:
• Mode wherein operation of the PLC is stopped
• Mode wherein operation of the PLC continues
In addition, there are errors with which the operation can be selected to stop or to
continue by the parameter setting.
(a) When an operation stop error is detected by the self-diagnostics, the operation
is stopped at the time of detection of the error, and sets the all outputs(Y) to OFF.
(b) When an operation continued error is detected, the only part of the program with
the error is not executed while the all other part is executed.
Also, in case of module verify error, the operation is continued using the I/O
address prior to the error.
When an error is detected, error occurrence and error contents are stored in the
special relay (M) and special register (D), so that in case of the continue mode, the
program can use the information to prevent any malfunctions of the PLC or
mechanical system.
Error descriptions detected by the self-diagnostics are shown in the next page.
REMARK
(1) As to the LED indication message, the order of priority of the LED
indication can be changed if CPU module is in the operation mode. (An
error code is stored in the special register)
(2) When the special relay M9084 is ON, checking on fuse blown, I/O
verification and the battery are not performed. (an error code is not stored
in the special register)
(3) The "Error indication of peripheral device" in the table of self-diagnostics
functions are messages indicated by the PLC diagnosis of peripheral
devices.