Mitsubishi Q Series User Manual page 221

7 ONLINE MODULE CHANGE
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(3) Data save
After module change, the buffer memory returns to default value (value read from
FeRAM). Saving and recovering the buffer memory contents is necessary to
continue previous operating states in changed module.
However, if recovery with sequence program or initial settings is possible, this
operation is not necessary.
The whole buffer memory contents that can be written are required to continue
the operating states. There are two following methods to save the buffer memory.
(a) Specify the buffer memory of module to be changed with [Read from PLC] -
[Device data] on GX Developer to read it.
(b) Monitor the buffer memory of module to be changed with [Buffer memory
batch monitor] on GX Developer and jot down the buffer memory contents.
Each operation should be performed before online module change, because they
cannot be performed after online module change has started. For operating
procedure, refer to Section 7.3.
(4) Wiring
The wiring should be performed after making sure that all external power supply
of current output has turned off.
MELSEC-Q
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