LSIS XBE-DC08A, User Manual

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Chapter 5 Datalog Function
5-23
5.3.8 Data Omission
Data omission refers to situation where normal data collection is not possible. If data collection interval is set too short, data
sampling might not be performed at every set interval, which in turn might cause data omission. Cases include the following.
(1) Buffer Excess
If data sampling condition is set too fast or too much data are being sampled, the speed of saving buffer memory values
into the temporary file in the SD memory may be slower than the data collection speed, which causes the buffer storage
to be exceeded and data omission. (5.11 see data processing time)
(2) Too Frequent File Conversion
Upon occurrence of file conversion condition, the temporary file should be converted to CSV file to create a new
temporary file. Meanwhile, the buffer memory values cannot be saved into the temporary file. Therefore, too frequent
occurrence of file conversion condition may cause the buffer memory storage to be exceeded, and thus leading to data
omission.
(3) Operation
While data log file is accessed through FTP, the buffer memory values cannot be saved into the temporary file.
Therefore, accessing large-volume files through FTP may cause the buffer memory storage to be exceeded, and thus
leading to data omission. When using FTP, please consider the data log performance (4 words / 20ms)
(4) Web Server Operation
In case of web server run with data log file, the SD memory saving performance may deteriorate, which makes it
impossible to normally save data accumulated in the buffer, which may cause data omission.
When using with a web server, please use caution in setting the parameter values, so as to avoid data omission.