File Handling Precautions - Mitsubishi Electric MELSEC-Q Series User Manual

6 FILES HANDLED BY BASIC MODEL QCPU

6.7.2 File handling precautions

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(1) Power OFF (or reset) during program operation
(a) If power is switched off during any file operation that will not cause a file
shift, the memory data will be indefinite.
(b) When the battery (Q6BAT) is used for backup on the Basic model QCPU,
switching power off during any of the following operations that will cause a
file shift will make the program memory data indefinite.
• File size change
• Arrange PLC memory
• New file creation
(2) Simultaneous access of the same file from multiple GX Developers
The Basic model QCPU allows access to a single file from a single GX
Developer only.
To make access from multiple GX Developers to the same file, start the
processing of next GX Developer after completion of the processing of current
GX Developer
MELSEC-Q
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