5
- 129
5.10 Redundant CPU Functions Restricted in Redundant System
5.10.1 Enforced ON/OFF of external I/O
5
(4) Operation When Control System/Standby System Is Powered Off and
Then On/CPU Module Is Reset and Then its RESET Switch Is Set to
Neutral Position
(a) In the backup mode
1) Operation when control system is powered off and then on/control
system CPU module is reset and then its RESET switch is set to neutral
position
System switching occurs when the control system is powered off/the control
system CPU module is reset.
The input/output of which forced ON/OFF has been registered remains the
ON/OFF status according to the forced ON/OFF information of the new control
system CPU module.
2) Operation when standby system is powered off and then on/standby
system CPU module is reset and then its RESET switch is set to neutral
position
If the standby system is powered off/the standby system CPU module is reset,
the forced ON/OFF information of the control system CPU module does not
change.
The input/output of which forced ON/OFF has been registered continues the
ON/OFF status according to the forced ON/OFF information of the control
system CPU module.
Table5.61 Operation When Control System Is Powered Off and Then On/Control System CPU Module Is Reset and Then
its RESET Switch Is Set to Neutral Position
Item
Module mounted on main base unit including Redundant CPU
Module mounted on remote I/O station
Input
Device X remains ON/OFF according to the forced ON/OFF information.
Output
External output ON/OFF is continued according to the forced ON/OFF information.
Table5.62 Operation When Standby System Is Powered Off and Then On/Standby System CPU Module Is Reset and Then
its RESET Switch Is Set to Neutral Position
Item
Module mounted on main base unit including Redundant CPU
Module mounted on remote I/O station
Input
Device X remains ON/OFF according to the forced ON/OFF information.
Output
External output ON/OFF is continued according to the forced ON/OFF information.