Omron SYSMAC CS1D-PD Series Operation Manual page 462

Error Processing
Fatal Errors
422
For the following errors, operation will stop for a Duplex CPU System in
Duplex Mode or in Simplex Mode, or for a Single CPU System.
Connect the CX-Programmer or a Programming Console to display the error
message (in the PLC Error Window on the CX-Programmer). The cause of
the error can be determined from the error message and related Auxiliary
Area flags and words.
A fatal error has occurred if the indicators have the following conditions during
operation in RUN or MONITOR mode.
Power Supply Unit
CPU Unit
Duplex Unit (with
error occurring on
active CPU Unit)
Note 1. I/O memory will be cleared when a fatal error occurs.
2. If the I/O Hold Bit is ON, I/O memory will not be cleared, but all outputs from
Output Units will be turned OFF.
POWER
RUN
ERR/ALM
INH
PRPHL
COMM
DPL STATUS
Active CPU Unit ACTIVE
indicators
CPU STATUS
Standby CPU Unit ACTIVE
indicators
CPU STATUS
Section 10-2
Lit green
Not lit
Lit red
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Lit green
Lit green
Not lit
Not lit
Not lit