Mitsubishi Electric MELSEC iQ-R-R00CPU, Руководство пользователя

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11 DATA LOGGING FUNCTION
11.16 Precautions to Take When Using the Data Logging Function
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Stopping/suspending data logging using CPU Module Logging Configuration Tool
After data logging is stopped or suspended from CPU Module Logging Configuration Tool, all the data in the internal buffer are
saved into the target memory. If a small number of records or a small file size is specified as part of the storage file switching
condition, saving data to the target memory may take longer.
Error that occurs when the data logging is started
Behavior when an error occurs at the start of the multiple data logging settings at the same time is as follows:
• If the start operation is performed by using CPU Module Logging Configuration Tool, the CPU module runs data logging for
the setting files that have been successfully registered.
• If the auto logging is started, the CPU module does not run any data logging session.
Behavior upon change of the internal buffer capacity
When the internal buffer capacity is changed during execution of the data logging function, note that:
• If the internal buffer capacity for the setting number of the running data logging is left empty to disable the capacity, an error
occurs when the data logging is stopped and restarted (write to the programmable controller does not cause an error).
• If the internal buffer capacity of the setting number of the running data logging is changed to a smaller value, data may be
lost when the data logging is stopped and restarted.
Trigger condition at the start operation of data logging
Ensure that the trigger condition is not met during the registration of the data logging settings by the start operation of data
logging. If the trigger condition is met, the data logging settings cannot be registered.
When file register is specified as device/label in condition specification
After registration of data logging, do not change the file name and block number of the file register file in the following cases;
the file register is specified as the device or the global label where the file register is assigned as the label for the condition
specification in the "Sampling" and "Trigger" settings. Doing so may possibly result in failure to successfully collect data
logging results.
When the data collection condition is set to "Time specification"
If "Time specification" is selected for the data collection condition, data collection is performed as an interrupt processing
operation and therefore special care should be taken when configuring the data collection interval, the data collection timing,
and the data logging processing time per scan. In the following cases, scans may take a longer time, possibly resulting in a
WDT error:
• The collection interval and the collection timing are so short that data logging is frequently performed during a single scan.
• The data to be collected is so much that the data logging processing time per scan is long.
Numbering of the storage files used during data logging
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If one or more numbered storage files already exist in the file storage folder
The new file is given a file name that uses a number incremented by one from the highest number among the existing files.
When the setting for files that has been completed to transfer is specified to delete in the file transfer setting, numbering to
new storage files starts from 1 because no files exist in the folder at the time of restarting data logging.
■ If one or more storage file folders exist but no storage files in them
A new file is stored into a folder with the lowest number and given the same number as the folder.
However, if there are 258 or more folders, a new folder is created and the file in it is given the same number as the new folder.
When the file that has been completed to transfer is specified to delete in the file transfer setting, the existing folders are
deleted if no files exist in the folders when the data logging stops. (The existing folders are not deleted while the data logging
is in progress.)