Rockwell Automation FactoryTalk View Site Edition Users Guide - Manual (Page 609)

23 • S ETTING UP TRENDS
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Plotting a value across the full width of the chart
Use horizontal lines on a trend chart to provide an orientation for your tag data.
For example, you can define upper and lower limits for a tag’s value, and then show the
limits as horizontal lines in the trend. When the value crosses one of the limits, the tag’s
condition is obvious on the trend.
The vertical position the pen in the trend depends on value of the tag, expression, or
constant used to define the pen. If the value changes, the position of the horizontal line
also changes.
To plot a constant value across the chart’s full width
1. In the Trend Properties dialog box, click the Pens tab.
2. Add a pen with a constant value.
When values for the pen are plotted across the full width of the chart, the pen shows as a
solid horizontal line.
To plot a tag or expression across the chart’s full width
1. In the Trend Properties dialog box, click the Pens tab.
2. Add a pen with a tag or expression that will determine the position of the pen line.