Omron CS1D DUPLEX SYSTEM - 10-2009 Operation Manual page 162

Duplex CPU Units
Note
Conditions for Mode Switching in a Duplex System (Reference)
Condition
When an Power interruption (when
operation the CPU Setting Switch
switching on the active CPU Unit is
error occurs switched from USE to NO
at the active USE).
CPU Unit.
Watchdog timer error
(CPU error)
Memory error
Cycle time overrun
Program error
FALS error
Fatal Inner Board error
(Process-control CPU
Units only)
When a Duplex bus error
duplex error
Duplex verification error
occurs.
During duplex initialization.
Standby CPU Power interruption (when
Unit the CPU Setting Switch is
switched from USE to NO
USE).
When one of the following
errors occurs: Watchdog
timer error, memory error,
cycle time overrun error,
program error, FALS
error, fatal Inner Board
error.
Mode Setting When set to SPL, and
Switch on when the Initial Switch is
Duplex Unit pressed.
When set to DPL, and
when the Initial Switch is
pressed.
When a non-fatal error such as a battery
error occurs.
When a fatal error other than an operation
switching error occurs.
126
1. When a duplex verification error or duplex bus error occurs when the power
is turned ON, the CPU Unit goes into "CPU standby" status.
2. The cause of the "CPU standby" is stored in A322 in the Auxiliary Area.
System Duplex Mode
operation
Operation Switched to
continues. Simplex Mode
Switched to
Simplex Mode
Switched to
Simplex Mode
Switched to
Simplex Mode
No change
from Duplex
Mode.
Operation
stops
Active/standby status
Active CPU Unit Standby CPU Unit
Power interruption Switched to active. (Oper-
ation continues.)
CPU stopped.
Remains active. Remains in standby.
(Operation contin-
ues.)
Switching between active and standby is dis-
abled.
Note If a cause of duplex switching occurs
during this interval, operation stops.
Remains active. Power interruption
(Operation contin-
ues.)
Remains in standby.
Remains active. Remains in standby.
(Operation contin-
ues.)
Remains active. Remains in standby.
Remains active. Remains in standby.
Remains active. Remains in standby.
Operation stops Operation stops
Section 3-1