Mitsubishi Electric MELSEC iQ-R-R00CPU - Switching to a Storage File

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11 DATA LOGGING FUNCTION
11.6 Steps Until the Collected Data Is Saved
Switching to a storage file
The data collected by data logging is temporarily stored in a stack file. The stack file can be switched to a storage file to free
the space in the SD memory card.
How file switching works
File switching works as follows:
1. The CPU module writes collected data into a stack file (such as LOG01.BIN).
2. It changes the file name when the storage file switching condition is met.
*1*2
3. It creates a new stack file.
4. It continues to write collected data into the newly created stack file.
*1 The file name format can be customized. ( Page 977 Save)
*2 The file number of the most recent storage file is stored in the special register (Latest storage file number).
File switching condition
The following table lists the setting items that can be used to specify the file switching condition.
*1 File switching occurs before the file grows beyond the specified size.
However, file switching occurs regardless of the setting when:
• the number of records has reached the maximum number;
• the file size has reached the maximum size;
• the CPU module is stopped or suspended/resumed: or
• data logging is started and there is an existing stack file.
Trigger logging does not require the configuration of these settings because the stack file is automatically
switched to a storage file after as much data as the specified number of records is written into the stack file.
SM1218 (logging data storage file switching in progress) can be used to check if storage file switching is in
progress.
Setting item Description
Number of records Specify the number of records within the following range.
• When the data storage destination memory is the SD memory card: 1 to 65500
• When the data storage destination memory is the function memory: 1 to 12000
File size
*1
Specify the number of kilobytes within the following range.
• When the data storage destination memory is the SD memory card: 10 to 16384K bytes
• When the data storage destination memory is the function memory: 10 to 1024K bytes
LOG01.BIN
LOG01.BIN LOG01_00000001.BIN
:
:
Stack file
Device data collection
Stack file
Device data collection
Storage file
File switching
CPU module
CPU module