The Historical Data Viewer Page
VTS provides a detailed, yet easy-to-use Historical Data Viewer page as a means for users to plot live and historical data on a graph, and manipulate that data for the purposes of data analysis.
The Historical Data Viewer page is shown in the following image:
As shown, the Historical Data Viewer page is primarily a large graph upon which you can view historical data that has been logged for the tags in your application.
Pens: Because data is plotted on a graph, the selected tags (and notes) that are to be plotted are referred to as “Pens”. Throughout this chapter, wherever you see the word “Pen”, what is meant is “A tag selected for display in the Historical Data Viewer”.
By default, VTS has been configured in such a way that you can instantly graph historical data for any basic input tag (analog input or digital input), simply by clicking the tag's associated drawing method. When you do so, a windowed version of the Historical Data Viewer page opens on top of the application page you are currently viewing. An example is shown below.
Note: Although you may certainly plot historical data for the output tags in your system, you must do so by adding them to the graph using the "Tag Selector" tool, rather than by clicking their drawing methods. Information on using the "Tag Selector" tool can be found in Add One or More Pens to the Historical Data Viewer Page Using the Tag Selector.
The Historical Data Viewer page also features a tabular view of tag data. An example is displayed below.
Plotting Live and Historical Data
Historical Data Viewer Page Elements and
Tools