Viewing Tabular Data

The GridView tab changes the graphical display to one showing tabular data.  An example of the grid view follows:

No pen legend is shown for the grid view.  The left-most column shows time values, followed by columns for all of the tags that have been selected.

It is important to note that the data values shown are interpolated from the raw data recorded from the tag. 

For example:  Given a logger tag on an analog input that is recording values once per hour.  You view a graph showing a 1 day time frame.  Only 24 data points were recorded during that day, but the HDV will show a smooth curve through those points and the matching grid view will display the interpolated numbers that make up that curve.   The actual tag values may have been quite different, but since data is recorded only once per hour it is impossible to know.

The opposite case also applies:  Given a tag whose data values are logged once per minute, 1440 points are recorded every day.  Not all of these points can be shown in a graph that displays a one-week view, thus data spikes may be lost from the displayed view.  Again, the grid view shows the interpolated points that make up the graph, not necessarily the actual points from the tag. For more information on retaining plot peaks (or data spikes), see: Modifying Analog Pen Properties elsewhere in this chapter and the configuration variable, HDVAnalogPenMinMaxVisibility in the Programmer’s Guide.

 

When viewing digital values in the grid view, you may see a message such as “76.6% Active” go by instead of the usual 0 or 1 values.  This message tells you the percentage of the displayed time period for which the tag’s status was non-zero.

 

To return to the graphical view, click on the PlotView tab.