Mitsubishi Electric MELSEC Q Series User Manual page 20

Precautions for using redundant system
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(4) Diagnostic time of CompactFlash card
(a) The Web server module executes diagnosis (including file restoration) of the
CompactFlash card when:
1) Power is turned OFF and ON, or the CPU module is reset.
2) The CompactFlash card is inserted while the power is ON.
(b) The diagnostic time of the CompactFlash card is lengthened if many files are
stored in the card.
It takes approx. 5 seconds for 100 files, and approx. 10 seconds for 1000
files.
(c) Since the following times may be lengthened due to too many files, delete
unnecessary files.
1) Rising time of the CompactFlash card setting status. (X1)
2) Web server module's ready time. (Rising time of the Module READY (X0))
(5) CompactFlash card formatting
(a) Use the formatting function of the Web server module to format the
CompactFlash card. (Refer to Section 6.10.2.)
(b) Do not format the CompactFlash card on Windows
If it is formatted on Windows
of the CompactFlash card.
(6) CompactFlash card lifetime (limited number of writes)
The CompactFlash card has its own lifetime (the limited number of writes).
For details, check the specifications of each product.
Since the lifetime of the CompactFlash card generally varies depending on its
free space, it is advisable to use the card with sufficient free space.
For the size of the data written to the CompactFlash card, refer to Appendix 7.2.
(1) Applicable base units
When using the Web server module in a redundant system, always mount it to an
extension base unit designed for redundant CPU/power supply systems.
The Web server module cannot be mounted to a main base unit in redundant
systems.
(2) Access target CPU setting
(a) If the Web server module is connected to a redundant CPU, it can access
only the CPU of its own station.
Access to the other station's CPU is not allowed.
(b) If the Web server module is connected to any other than redundant CPUs, it
cannot access redundant CPUs on other stations.
(3) Tag setting
(a) When "Execute at high speed" has been selected for Sampling in Tag
setting, always create two user-setting system areas of the same size in the
redundant CPUs on both systems. (Refer to Section 6.3.3 REMARKS.)
(b) If system switching occurs in the redundant CPUs, tag collection may stop
for approx. 15 seconds.
® by mistake, recover it according to the manual
®
.
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