Omron CX-SUPERVISOR - V2.0, User Manual

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CHAPTER 11 – Data Logging OMRON
Page 180 Release 2.0
Data Logging at Runtime
Overview
All data logging is performed on Items, which are stored in a Data Set. The System can contain
many Data Sets and each Data Set can contain many Items. Each Data Set will have its own set of
files when the System is run (see the chapter 11, File Management). The amount of data that is
stored in a single Data Set file is determined by the specified period when the Data Set is created.
File Management
Data Logging Directory
All data log files are stored in the directory “Data Logging” separate from the CX-Supervisor files.
This directory is created automatically when the project runs for the first time. A sub-directory is
used as a safeguard against the accidental deletion of important files by the automatic purge
mechanism and to prevent the project directory from becoming cluttered with data files.
For example, if the CX-Supervisor project is in a directory called
C:\CX-Supervisor\Project
then,
when the project runs for the first time a new directory called
C:\CX-Supervisor\Project\Data Logging
will be created to hold the data log files.
Data Logging Files
Each Data Set has its own set of files. The following conventions have been adopted in order to
identify the various files and add time and date information.
Data Log files are assigned the file extension .dlv “Data Log Values” and the format of the filename
is:
<Data Set Name><Time Stamp>.dlv
The Time Stamp is in the format: [YYYY MM DD HH]”
where YYYY = Year in the form 1999
MM = Month in the form 01 (January)
DD = Day of the month in the form 01 – 31
HH = Hours in the form 00 –23
Daylight time saving is automatic.
For example:
Data Set 1 Miller[1999012015].dlv
A new log file will be created automatically whenever the preceding file has expired the timestamp.
The timestamp is also used to distinguish between files in the same Data Set. The time period for
each file is determined by the options selected when the Data Set was created. The minimum time
period for a Data Set file is one hour commencing on the hour.