Precautions For The Data Logging Function - Mitsubishi Electric MELSEC-L Series User Manual

6.8

Precautions for the data logging function

The following describes precautions for using the data logging function.
(1) Exclusive processing
(a) Sampling trace during data logging execution
Sampling trace is not executable during data logging execution.
(b) Data logging during sampling trace execution
Sampling trace continues normally, and an error is detected in data logging.
(c) Online change during data logging execution
When a value is specified for "Step No." in "Sampling" or "Trigger", online change continues normally, and an
error is detected in data logging.
(d) Data logging during online change execution
When a value is specified for "Step No." in "Sampling" or "Trigger", online change continues normally, and an
error is detected in data logging.
(e) CPU module change by using an SD memory card during data logging execution
CPU module change by using an SD memory card is not executable during data logging execution.
(f) Data logging during execution of CPU module change by an SD memory card
CPU module change by using an SD memory card continues normally, and an error is detected in data logging.
(g) PLC memory formatting during data logging execution
While sampled data are being saved from the buffer to an SD memory card, PLC memory formatting cannot be
performed to the memory where the setting file of the currently executing data logging is stored.
(h) Data logging during execution of PLC memory formatting
PLC memory formatting continues normally, and an error is detected in data logging.
(2) Multiple trigger logging settings
In multiple trigger logging settings, the following causes an error at start of data logging.
• Specifying a device in "Condition specification" of "Trigger".
(3) Holding and clearing the data logging setting
The data logging setting registered to the CPU module is latched. Even if the CPU module is powered off and
then on or is reset, the data logging can be performed again with registered setting data. However, the data
logging status is cleared when the storage destination is an SD memory card and any of the following conditions
is met. Write the setting data again.
• The CPU module is powered off and on or is reset with the SD memory card removed.
• When the CPU module change function with SD memory card is used, the CPU module is powered off and
on or is reset with no setting data stored in the SD memory card. (If the SD memory card after replacement
contains setting data, registration is performed with the data.)
CHAPTER 6 DATA LOGGING FUNCTION
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