101BExtended instructions
8.7 Data logging
S7-1200 Programmable controller
302
System Manual, 11/2011, A5E02486680-05
8.7.3
Working with data logs
The data log files are stored as comma separated value format (*.csv) in persistent flash
memory. You can view the data logs by using the PLC Web server feature or by removing
the PLC memory card and inserting it in a standard PC card reader.
Viewing data logs with the PLC Web server feature
If the PLC PROFINET port and a PC are connected to a network, then you can use a PC
web browser like Microsoft Internet Explorer or Mozilla Firefox to access the built-in PLC
Web server. The PLC may be in run mode or stop mode when you operate the PLC Web
server. If the PLC is in run mode, then your control program continues to execute while the
PLC Web server is transferring log data through the network.
Web server access:
1.
Enable the Web server in the Device Configuration for the target CPU (Page 474).
2.
Connect your PC to the PLC through the PROFINET network (Page 474).
3.
Log in to the built-in Web server (Page 476).
4.
Download the recent records, all records, clear records, or delete log files with the "Data
Log" standard web page (Page 486).
5.
After a copy of a data log file is downloaded to your PC, you can open the .csv file with a
spreadsheet application like Microsoft Excel.
Viewing data logs on a PLC memory card
If the S7-1200 CPU has a "Program" type S7-1200 memory card inserted, then you can
remove the memory card and insert the card into a standard SD (Secure Digital) or MMC
(MultiMediaCard) card slot on a PC or PG. The PLC is in stop mode when the memory card
is removed and your control program is not executed.
Use the Windows file explorer and navigate to the \DataLog directory on the memory card.
All your \*.csv data log files are located in this directory.
Make a copy of the data log files and put the copies on a local drive of your PC. Then, you
can use Microsoft Excel to open a local copy of a *.csv file and not the original file that is
stored on the memory card.
CAUTION
You can copy, but do not modify or delete data log files on a S7-1200 memory card using a
PC card reader
The standard Web server data log page is the recommended tool for viewing, downloading
(copying), clearing (delete the data), and deleting data log files. The Web server manages
the memory card files for you and helps prevent accidental modification or deletion of data.
Direct browsing of the memory card file system by the Windows Explorer has the risk that
you can accidentally delete/modify data log or other system files which may corrupt a file or
make the memory card unusable.