Omron CS1D DUPLEX SYSTEM - 10-2009 Operation Manual page 487

Online Replacement of I/O Units, Special I/O Units, and CPU Bus Units
5 Units removed.
Units to replace:
5 Units
Maintenance
Start Bit
(A80015)
Turned ON by user
before removing Units.
Online
Replacement
Completed Bit
(A80215)
The Maintenance Start Bit will be turned OFF automatically when the Online
Replacement Completed Bit (A80215) is turned ON to restart data exchange
between the replacement Unit and the CPU Unit.
When two or more Units have been removed and replacement Units are being
added to the system in order, the Maintenance Start Bit will be turned OFF
when data exchange is restarted with the last Unit that was replaced.
Example
Mount 2 Units
and turn A80215
from OFF to ON.
Units to replace:
3 Units
The CPU Unit will not detect errors occurring in Units,
including Units not being replaced. (See note.)
Restart data
exchange with
2 Units.
Note If you want to detect errors in other Units before all of the Units have been
replaced online, turn OFF the Maintenance Start Bit.
Online Replacement Completed Bit (A80215)
When the Unit Removal without a Programming Device function is selected
and a Unit has been installed during operation without a Programming Device,
the Online Replacement Completed Bit (A80215) must be turned ON in order
to restart the data exchange between the replaced Unit and the CPU Unit.
When turning this bit ON externally, allocating the bit to an external switch or
turn the bit ON from a PT. (The bit can also be turned ON from the CX-Pro-
grammer or a Programming Console.)
Note Do not turn ON the Online Replacement Completed Bit (A80215) continu-
ously from the ladder program or other source. If the Unit is mounted while the
Online Replacement Completed Bit is ON, the PLC (CPU Unit) may stop
operating.
If two or more Units have been removed at one time, data exchange will
restart only with the newly mounted Units when the Online Replacement
Completed Bit is turned ON. Therefore, the Online Replacement Completed
Bit must be turned ON each time that Units are mounted.
Mount 2 more Units Mount 1 more Unit
and turn A80215 from and turn A80215
OFF to ON. from OFF to ON.
Units to replace: Replacement
1 Unit complete
Restart data Restart data
exchange with exchange with
2 more Units. 1 more Unit.
Section 11-4
The system automatically
turns the bit OFF when all
of the Units have been
replaced and data
exchange has restarted
with all of those Units.
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