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ONLINE MODULE CHANGE
7 ONLINE MODULE CHANGE
To perform online module change, read the following manual.
• QCPU User's Manual (Hardware Design, Maintenance and Inspection)
(1) Perform an online module change by operating GX Developer.
(2) To ensure ease of offset/gain re-setting, there is a user range save/restoration function
that is performed by executing the dedicated instruction or read/write from/to buffer
memory.
(1) Perform an online module change after making sure that the system outside
the programmable controller will not malfunction.
(2) To prevent an electric shock and malfunction of operating modules, provide
means such as switches for powering off each of the external power supply
and external devices connected to the module to be replaced online.
(3) After the module has failed, data may not be saved properly. Referring to
Section 3.4.23, therefore, prerecord the data to be saved (offset/gain values
of the industrial shipment settings and user range settings in the buffer
memory).
(4) It is recommended to perform an online module change in the actual system
in advance to ensure that it would not affect the other modules by checking
the following:
• Means of cutting off the connection to external devices and its
configuration are correct.
• Switching ON/OFF does not bring any undesirable effect.
(5) Do not install/remove the module to/from the base unit more than 50 times
after the first use of the product. (IEC 61131-2 compliant)
Failure to do so may cause malfunction.
(Note)
The dedicated instruction cannot be executed during an online module change. When
using the dedicated instruction to execute save/restoration, therefore, execute
save/restoration in the other system
*1
.
If the other system is unavailable, execute restoration by performing write to the buffer
memory.
*1: If the module is mounted on the remote I/O station, execute save/restoration in the other system
mounted on the main base unit. (Save/restoration cannot be executed in the other system
mounted on the remote I/O station.)