Operation and Data Access
Trend
The submenus of “Trend” show all measured values of the respective device as daily chart. One group always contains three measured values of the device. These measured values are stored every 5 minutes in a log file on the CompactFlash board.
In these submenus, it is also possible to display log files from the past by selecting the respective day, month and year. The selected day will be shown on the chart.
Log files
The log files are text files in ASCII format which can be processed by the other standard programs (e.g. MS Excel). The log files are located in the directory “ARCH”. The log file names are compounded as follows:
0304 A 00.TXT
Year
Month
For each bus user, a log file is created per month. The size of the log file depends on the individual bus user. A maximum capacity of 500 KB is required per bus user and month, i.e.: a data volume of 6MB is expected per year for each bus user. There are different sizes of CF cards available (see chapter 6.1).
The log files must be backed up regularly (on another drive in a PC), and the older files must be deleted. If the memory capacity of the CF card is exhausted, the ChemWeb Server cannot be operated anymore!
The CF card must also include the firmware of the ChemWeb Server. Therefore it is not allowed to modify or delete any other files from the CF card than the log files described above! This would cause data loss and failure of the ChemWeb Server!
The CompactFlash card may only be removed and reinserted if the ChemWeb Server is switched off! The ChemWeb Server will not work without the CompactFlash card!
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