Mitsubishi MELSEC Q series User Manual page 69

(3) Storage location of saved files
A folder is created under the destination folder, and saved files are stored in the folder. Up to 256 files can be
stored in each folder. (When the maximum number of files has been reached, a new folder is created in the next
file switching, and the file storage location after file switching is changed.)
The number of files that can be stored in a destination folder is set within the range of 1 to 65535.
(4) When the maximum number of files to be saved is exceeded
Either of the following can be selected in the case of exceeding the maximum number of files to be saved. (
Page 127, Section 8.4.12)
• Overwrite
• Stop
(a) When "Overwrite" is selected
After the number of saved files is reached, the oldest file with the smallest number is deleted and a new file with
"the largest number plus one" is created to continue data logging. Also, as a result of file deletion, if no file
exists in a folder, the folder will be deleted.
(b) When "Stop" is selected
The operation differs depending on the following timing.
Timing
Files more than the specified number of saved files
At start of data logging
exist when data logging is started.
File switching occurs due to the timing set in the File
During execution of data
switching timing setting, and because of this, the
logging
specified number of saved files is reached.
The number of saved files is calculated with the file numbers as follows.
(when no file is deleted among the saved files of the smallest to the largest numbers)
Latest file number - Oldest file number + 1
Condition
When the start is instructed from the configuration tool, an error
message is returned and data logging is not executed.
When the start is instructed from any other than the configuration tool,
the special relay (Data logging error) turns on, and information on the
cause of the error is stored in the special register (Data logging error
cause). Data logging is not executed.
The data logging is completed and stopped. The special relay (Data
logging completion) turns on.
CHAPTER 6 DATA LOGGING FUNCTION
Operation
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