Omron CS1D DUPLEX SYSTEM - 10-2009 Operation Manual page 55

Specifications
Item
Duplex CS1D Duplex Mode
CPU Units
(Supported
only in Duplex
CPU Sys-
tems)
Operation of the two
CS1D CPU Units in
Duplex Mode
Operation switching
errors
Duplex errors
Automatic recovery
to duplex operation
Hardware condi-
tions for the two
CS1D CPU Units in
Duplex Mode
Software conditions
for the two CS1D
CPU Units in Duplex
Mode
CS1D CPU Unit
online replacement
Specifications
A Duplex CPU System can be operated in either of the fol-
lowing two modes:
Duplex Mode (DPL)
The system operates with CS1D CPU Units and CS1D
Power Supply Units in duplex status.
Simplex Mode (SPL)
The system operates with just a single CS1D CPU Unit.
Hot standby method: One of the two CS1D CPU Units
actually controls operations, and the other is on standby
as a backup. The two CS1D CPU Units have the same I/O
memory, and parameters (PLC Setup, I/O tables, etc.),
and both run the same user's program.
Their operation differ in the following points:
The active CPU Unit executes I/O refreshing and all event
servicing.
The standby CPU Unit handles file accessing (read only)
and FINS command execution event servicing (read only).
Power interruptions If any of the errors listed on the left
(CPU operation set- occur in the active CPU Unit, stop-
ting switch: NO ping operation, the standby CPU
USE), CPU errors, Unit automatically switches to active
memory errors, pro- status and takes over control. At the
gram errors, cycle same time, the mode is switched to
time overrun errors, Simplex Mode. The CPU Unit where
FALS executions, the error occurred can be replaced
fatal Inner Board without stopping system operation.
errors
Note A fatal Inner Board error
Duplex bus errors If either of the errors listed on the
left occurs in Duplex Mode, the
Duplex verification
active CPU Unit remains the same
errors
and operation is switched to Sim-
plex Mode.
After operation has been switched from Duplex Mode to
Simplex Mode as a result of any of the operation switching
errors listed above, operation is automatically returned to
Duplex Mode when it is determined that the cause of the
error has been cleared. Automatic recovery to duplex
operation must first be enabled in the PLC Setup. (The
recovery can be repeated up to ten times.)
Identical models must be used for the two CS1D CPU
Units.
The same user program areas must be used.
The same parameter areas (PLC Setup, etc.) must be
used.
The same Inner Board data must be used (Process-con-
trol CPU Units only).
Only the functions that can be executed by both CPU
Units can be used (when the unit versions of the CPU
Units are not the same).
The CS1D CPU Unit where the error occurred can be
replaced online by turning OFF the power to only that Unit
(i.e., setting the CPU operation switch to NO USE).
applies only to Process-con-
trol CPU Units.
Section 2-1
Reference
1-2-1 CS1D Duplex
Systems
3-1-1 Duplex CPU Sys-
tems
3-1-2 Errors Causing
Operation to Switch to
the Standby CPU Unit
3-1-3 Duplex Errors
3-1-4 Automatic Recov-
ery to Duplex Opera-
tion by Self-diagnosis
3-1-1 Duplex CPU Sys-
tems
3-1-1 Duplex CPU Sys-
tems
3-1-6 Duplex CPU
Units with Different Unit
Versions
11-3 Replacing a CPU
Unit
19